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HP 4945A User's Manual

1. HEWLETT PACKARD HP 4945A Transmission Im Operating Manual Riv 10044 THF 1004 CE So MEO 78 SYSTEMS i OPERATING MANUAL HP 4945A TRANSMISSION IMPAIRMENT MEASURING SET SERIAL NUMBERS This manual applies directly to instruments with serial numbers prefixed 25214A For additional important information about serial numbers see INSTRUMENTS COVERED BY THIS MANUAL in Section I Copyright Hewlett Packard Company Colorado Telecommunications Division 1985 2070 Centennial Blvd P O Box 7050 Colorado Springs CO 80933 All Right Reserved Manual Part No 04945 90023 Printed Pages Part No 5957 4454 Binder Part No 9282 0987 Microfiche Part No 04945 90024 Printed May 1985 Printed in U S A PRINTING HISTORY New editions of this manual will incorporate all material updated since the previous editions Update packages may be issued between editions and contain replacement and additional pages to be merged into the manual by the user Each update page will be indicated by a revision date at the bottom of the page A vertical line in the margin indicates the changes on each page Pages which are rearranged due to changes on a previous page are not considered revised The manual printing date and part number indicate its current edition The printing date changes when a new edition is printed The manual part number changes when extensive technical changes are incorporated November
2. List of Illustrations Figure 3 22 3 23 3 24 3 25 4 1 4 2 4 3 4 5 h 6 4 7 4 8 4 9 4 10 4 11 4 12 4 13 4 14 4 15 4 16 4 17 4 18 4 19 LIST OF ILLUSTRATIONS con t Page The P AR Measurement Men u anreisen 3 h8 The Return Loss Measurement Menu eee tns 3 50 The Programmable Sweep Menu for Return Loss eee 3 52 Master Slave Test Set Upi uud 9 REY OE CS P PEWER E ENS T a 3 62 Input 0 tp t eit TER II Vie cad pd el xa eee REE S eye ee e i e US 4 2 Level and Frequency Measurement vnnd naar ern h 3 Message Circuit Noise Measurement cecinere nnn 4 6 C message Weighting Characteristics 4 won e Rn 4 7 3 kHz Flat Weighting Characteristiess s acacs us es ar REY RR 4 8 15 kHz Flat Filter Weighting Characteristics er ane 4 8 Program Filter Characteristic cceeee irren 4 9 50 Kbit Filter Charasteriticss s aae Ex e ET AR RAO Ea does 4 9 Notch Filter Character 28T 188 ou ses Ck a Pede et 4 10 Noise to Ground Related to Message Circuit Noise 4 11 Impulse Noise Hits and Dropouts Waveforms lees 4 14 Impulse Noise Hits and Dropouts sense an m 4 16 Effects of Phase Jitter and Amplitude on Holding Tone 4 19 Phase and Amplitude Jitter Measurement cler nn 4 20 Phase Versus Frequency Relationship cccessceees reer 4 21 Envelope Delay WacdlOoXHErL bush une d xo e ca wn EIU E d C AR RE od 4 22 AM
3. eee hen 5 3 HP IB Messages and HP 4945A Responses cleeeee leeren 5 9 HP IL Loop Messages and Module Responses eee 6 6 Measurement Results and Headers iis cscs es sus sen ne a 8 2 Diagnostic Mg 8S sss eet Lede eee ee DESEE ee LU E qan ee A 6 Stopron Cond itio a oe eee ee ev ca acp eee eS SSS WE dcs A 7 HP h9h5A General Information CHAPTER I GENERAL INFORMATION INTRODUCTION This Operating Manual contains information required to install and operate the HP 4O45A Tranmission Impairment Measuring Set TIMS Figure 1 1 shows the HP 4945A and the accessories supplied with the instrument Throughout the remainder of this manual the HP 945A will be referred to as the HP 4O4SA or the instrument Listed on the title page of this manual is a microfiche part number This number can be used to order 4 X 6 inch mircofilm transparencies of this manual Each microfiche contains up to 96 photo duplicates of the manual pages The microfiche package also includes the latest Manual Changes supplement SPECIFICATIONS instrument specifications are listed in Table 1 1 These specifications are the instrument s warranted performance Supplemental characteristics shown in italics are intended to provide information useful in applying the instrument by giving typical but non warranted performance parameters SAFETY CONSIDERATIONS This product is a Safety Class 1 instrument provided with a protective earth terminal The ins
4. 2 2 HP h9h5A HP IB Operation DEVICE A Able to talk listen and control Data Bus e g HP85 8 signai lines DEVICE 8 Able to taik and listen Data Byte Transfer Lis HANDSHAKE Lines 3 signal lines e g DEVICE C Oniy able to listen General interface Management Management CONTROL Lines 5 signal lines DEVICE D Only able to talk IFC HP 1B Signal Lines Figure 5 2 Interface Connections and Bus Structure 5 h HP LIUSA HP IB Operation COMMUNICATION CAPABILITY Devices on the bus fall into three basic catagories talkers listeners and controller Talkers are devices which send information on the bus when they have been addressed Only one talker at a time can be on the bus Listeners are devices which receive information sent on the bus when they have been addressed Ther can be multiple listeners on the bus Controllers are devices that can specify the talker and listener s for an informa tion transfer The controller can be an active controller or a system controller The active controller is the current controlling device on the bus The system controller can take control of the bus even if it is not the active controller Each system can have only one system controller even if several controllers have system control capability DATA INPUT AND OUTPUT MODES There are four commands that control the output of data
5. This softkey selects the mode of operation e g OFF MASTER or SLAVE If master slave mode is selected this softkey will determine the direction of test e g MASTER TO SLAVE or SLAVE TO MASTER Not Used HP h9l5A Operation Calibration The HP A9l5A has the capability of calibrating the major circuitry in the instru ment To perform the calibration procedure Press the SET UP hardkey e Press the CALIBRATE SELF CHECK softkey 1 e Press the CALIBRATE softkey 6 The message CALIBRATING will flash on the display while this is in progress If there are any problems refer to the service Manual To Set Up the Transmitter and Receiver Configuration 1 gu Set the MASTER SLAVE softkey 46 to read OFF in the parentheses Press the TRMT RCVR SET UP softkey 2 The menu shown below will appear Set each of the softkeys to the appropriate settings 09 28 83 10 42 AN A B TRHT INP E TRHT RCVR SET UP 600 CURRENT SET UP RCVR IMP 600 TRHT IHPEDANCE _ REYR IMPEDANCE it RCYR TERN RCVR TERH BRDG BRDGCTERID SF SKIP OF Se YOICE BAND LIHIT OFF SF SKIP 4 TRHT HOLD COIL F WFF VOICE BAND LIMIT OFF RCVR HOLD COIL HP h9h5A Operation This softkey sets the transmitter termination impedance The selections it cy cles through are 135 600 900 and 1200 ohms Select the impedance that matches the line to which the transmitter is connected This softkey sets the recei
6. 7 Not Used 3 52 8 HP HOUSSA Operation This softkey will return you to the return loss menu Note Due to the amount of time the receiver of the HP 495A needs to correctly measure return loss some points will not be displayed when using the medium or fast sweep rates General instructions 2 Wire Return Loss The HP 4945A contains an internal resistive hybrid which is used to measure the im pedance mismatch of a 2 wire circuit The internal hybrid is on the transmit side of the HP 49454 1 es Connect the line under test to the TRMT terminals Press the TEST SELECT hardkey Press the RETURN LOSS softkey 8 The Return Loss menu will be displayed Press the 2 4 WIRE softkey 1 until 2 WIRE appears in parentheses Select the appropriate reference impedance by pressing REFERENCE IMP softkey 7 until the desired selection amp ppears in parentheses 1f you want to use your own reference impedance press the softkey until EXT appears in parentheses The reference impedance should be connected to the jacks on the rear panel of the instrument Note The 600 and 900 ohm selections are each in series with a 2 16 uF capacitor s Note When using either of the internal reference impedances the EXTernal reference jacks are connected in parallel with the internal reference This is for the purpose of adding shunt capacitance e g NBO Network Build Out capacitance WARNING DO NOT place a de voltage acro
7. 7 dBmO0 is assumed and the return loss results are ad justed accordingly Select the desired test signal by choosing between softkeys 2 through 6 If performing sine wave return loss select the measurement frequency using the FREQuency hardkey 3 5h HP 49h5A Operation Note The HP 4945A automatically begins transmitting a 2150 Hz tone when SINE WAVE return loss is accessed This will disable any echo suppressors on the line Also the HP 4OL45A has the programmable sweep capability which comes up on softkey 8 after SINE WAVE return loss has been Selected This is explained in the previous section 6 Adjust the output level using the LEVEL hardkey to the level desired in dBmO referenced to TLP T If the transhybrid loss of the circuit is known press HYBRID LOSS and enter the appropriate value using the DATA ENTRY keys If it isn t known short the 2 wire arm of the hybrid under test Note the reading on the display and enter this reading as indicated above Don t forget to remove this short before proceeding 8 Observe the readings displayed if you are using 2 instruments to perform this measurement If you are using 2 instruments to perform this test you must set the transmit level on both even though only one transmitter is being used The HP 49454 at the receive side must know what the transmit level was in order to perform the return loss calculation Also make sure the impedances on both instruments are
8. Number of times self check has passed Number of times self check has failed 8 13 HP h9h5A I O Module Codes I O MNEMONIC COMMANDS The following list of mnemonics are the codes that the HP 4945A will respond to over the three interfaces They are three character mnemonics plus any data entry and a delimiter which will be a semicolon or linefeed HP IL may use a colon also Em bedded spaces and carriage returns will have no affect on the decoding of the mnemonics Any time a semicolon or a linefeed is received the module attempts to decode a mnemonic and the decoder is reset Syntax Explanation of Keystroke Sequences The following strings are for illustration purposes only To program the instrument the mnemonics must be used The code is used to specify the state of a softkey for example hl sets softkey Ken B to state 1 The data entry keys on the front panel are encoded as ASCII 0 through 9 and and are represented in the table of mnemonics as an when data is to be entered At the end of a data entry sequence delimited with or Lf the code for enter E is sent Those mnemonics followed by a plus sign can be accessed from more than one menu Therefore the last measurement made using a specific mnemonic must be known If the last measurement made uses the already selected mnemonic the test select menu cannot be accessed Rather it is assumed that the correct menu is displayed and the proper softkeys
9. Default conditions set the transmit 10 OUTA and receive impedances to 900 ohms 11 LFO Go to level frequency 12 OUTA 13 FREQUENCY RUN Print the label for the printout 14 PRA 15 ADV Linefeed the printer 16 REL LEVEL Label the columns 17 ACA 18 FMT Right and left justify columns 19 FREQUENCY 20 ACA 21 ADV Print the labels 22 ADV Linefeed 23 PSE Wait a moment to get reference settled 24 ZLV t Zero the level 25 OUTA 26 03601 Set up the number of loops and the 27 STO 01 increment in register 00 28 204 Set up th starting frequency 100 Hz 29 STO 01 in register 01 6 10 Sample Program con t Measurement loop 30 LBL FLOOP 31 FRO 32 RCL 01 33 ENTER 34 100 35 36 STO 01 37 FIX 0 38 STO 02 39 ARCL 02 LO OUTA li EXC h2 OUTA 43 FIX 1 hh IND 45 ACX h6 FMT 47 IND 48 IND 19 IND 50 ACX 51 ADV 52 IND 53 IND 5h IND 55 ENTER 56 0 57 X Y 58 GOTO ERROR 59 IND 60 ISG 00 61 GOTO FLOOP Program is done do cleanup 62 ADV 63 ADV 6h ADV 65 LOCAL 66 GOTO END Ten um ym tee auu e 0e o om 99 a me omm bow em pam ouw amm onu pow amn m omm oma HP h9h5A HP IL Operation Loop 37 times Program frequency to a value equal to the contents of register 01 plus 100 Hz Load new value back into register 01 Get rid of tenths Store the frequency in register 02 and append it as an alpha string into the
10. Following is a sample command that would dial the number 9 pause 1 800 987 6543 C399 SCl13 SC1 EXC ENDST 0 SCh9 SC1 EXC ENDST 0 SCh1h SC1 EXC ENDST 0 SCh1 SC1 EXC ENDST 0 SCh8 SC1 DXC ENDST 0 SCli10 SC1 EXC ENDST 0 SCh10 SC1i EXC ENDST 0 SCh9 SC1 EXC ENDST 0 SCh8 SC1 EXC ENDST 0 SChT SCi EXC ENDST 0 SCh6 SC1 EXC ENDST 0 SCh5 SC1 EXC ENDST 0 SChh SCl EXC ENDST 0 SCh3 SC1 EXC ENDST 0 gt To dial the number the controller would then send SCh16 SC1 EXC ENDST 0 WAIT FOR PBX RESPONSE SC415 SC1 EXc lt ENDST 0 gt 9759 HP 4O4SA Measurement Principles CHAPTER IV MEASUREMENT PRINCIPLES INTRODUCTION This section describes the principles of all measurements made by the HP 4945A Included are explanations of the need for the measurements plus the effect of cer tain voice channel parameters on data transmission Block diagrams and functional descriptions are provided to explain the HP 4945A input output switching and the different measurements that the test set make For further information concerning the voice channel measurements described in this section refer to the following Bell System Technical References PUB 41008 Analog Parameters Affecting Voiceband Data Transmission Description of parameters and PUB 41009 Transmission Parameters Affecting Voiceband Data Transmission Measuring Techniques These publications are available from Distr
11. Parity None Even Odd Mark Space Stop Bits 1 2 Word Length 7 8 HP 4945A RS 232C Operation To change or check the function settings press the SET UP key and then select the I O PORT SET UP Press the appropriate softkey until the desired selection appears The selection changes each time the softkey is pressed The following functions are programmable via mneumonic commands from an external device Echo On Off Local Lockout In effect Local Device Status Device Identification FULL DUPLEX No Handshake This handshake uses only Transmitted Data Received Data and Signal Ground Both the I O module and the external device are ready to receive data at all times The normal command string length however must never exceed the buffer size of 128 characters Data Terminal Ready and Request to Send will be asserted Data Set Ready Clear To Send and Received Line Signal Detected carrier detected will be ignored Data Terminal Ready Data Set Ready XXXXXXXX don t care XXXX Request To Send Clear To Send XXXXRARAAR don t care XXXX Received Line Signal Detected XXXXXXXX don t care XXXX Transmitted data NOST ACIE PONES NUS valid Received data E ge Teena tere ee valid 3 HP h9h5A RS 232C Operation Full Handshake This handshake uses Transmitted Data Received Data Signal Ground Data Terminal Ready Data Set Ready Request To Send and Clear To Send When the module is ready to operate it wil
12. R W error A10 U505 Receiver STACK RAM 1000 17FF R W error A10 U503 System receivr SHARED RAM dynamic R W error Ail U20h System RAM bank 0 2000 27FF R W error A13 U502 Character RAM bank 0 2800 2BFF R W error 413 0503 Attribute RAM bank 0 2C00 2FFF R W error A13 U306 Display RAM bank 0 3000 37FF R W error RAM bank 0 3800 3FFF R W error A13 U305 Display RAM bank 0 h000 hTFF R W error A13 U205 Display RAM bank 0 800 hFFF R W error A13 U203 Display RAM bank 0 5000 57FF R W error A13 U102 Display RAM bank 0 5800 5FFF R W error A9 U600 Transients RAM R W error A12 UhOh System RAM 1h00 1BFF R W error A12 U106 U107 System RAM 1C00 1FFF R W error A11 U606 Programmable timer error All UTO3 PIA error Not used 12 U308 Real time clock error A13 UTO2 CRT controller error System IRQ error system IRQ line is held low Receiver fails to write anything into SHARED RAM A10 U503 Receiver writes incorrectly into SHARED RAM A10 U503 Receiver does not respond by pulling on the system IRQ line P1 pin 9 on A10 and A11 System IRQ error system IRQ line driven by A10 does not function properly P1 pin 9 on A10 and A11 Power on self check data received from the receiver processor was sent with a bad checksum Receiver digital bus bad cannot talk to boards Ay through AT and A9 Receiver cannot talk to Al Receiver cannot talk to A5 Receiver cannot tal
13. m Lu N zZ O H uj a 10 Hz 100 Hz 1 kHz 10 kHz 100 kHz FREQUENCY Figure 4 6 15 kHz Flat Filter Weighting Characteristic 4 8 HP 49454 Measurement Principles 200 300 400 600 800 1000 FREQUENCY IN Hz Figure 4 7 Program Filter Characteristic gt oo RESPONSE dB 1K FREQUENCY Hz Figure 4 8 50 Kbit Filter Characteristic 4 9 HP h9h5A Measurement Principles Noise With Tone The noise with tone mode allows measurement of signal to noise ratio The noise with tone measurement is used to condition compandors and quantizers in the trans mission system to their normal operating levels for continuous data signals There fore noise levels are received which duplicate levels present under operating conditions To make this measurement a 100h Hz test frequency holding tone is transmitted at data level At the receiving TIMS the 1004 Hz holding tone is selectively attenu ated by gt 50 dB using a notch filter all frequencies between 995 Hz and 1025 Hz are attenuated by 50 dB The remaining received signal noise is passed through one of the weighting filters for measurement The received noise level is displayed in units of dBrn Figure 4 9 illustrates the notch filter characteristic Signal To Noise Ratio The signal to noise ratio of the voice channel under test is determined by comparing the noise with tone level with the holding tone level This measurement is done automatic
14. 14 15 16 Results Displayed Should Be 0 0 53 0 US 39 5 2 7 here 2140 0 0 0 0 2 0 0 0 1 0 3 0 3 0 1 0 GB 0 99 0 dB 1 0 dB 1 0 daB 0 8 dB 1 0 dB 1 0 dB 0 5 dB 0 5 dB 0 5 dB 0 5 dB 0 5 dB 0 5 dB 0 5 dB 0 5 dB not used Test 1000 Hz 1010 Hz 862 Hz 1182 Bz 10 0 kHz 20 0 kHz 60 Hz hoo Hz 1000 Hz 400 Hz 1000 Hz 1450 Hz 700 Hz 1000 Hz 1300 Hz A 20 Filter No filter Notch Notch Notch 10 kHz 10 kHz 60 Hz 60 Hz 10 dB Phase Jitter Phase Jitter Phase Jitter Transient Transient Transient For the phase jitter filter All measurements are made relative to data All tests are done with a 600 ohm Path HP 4945A Operating Verification Diagnostics Mode 14 MODE 14 At and A18 Check A1 A2 A4 A5 A17 A18 This mode tests the amplifier attenuators input stage and terminations on Al and the RTL transformer and RTL bridge on A18 Segments 1 2 and 3 use the A17 test signal as the signal source The other segments use the two wire return loss path from the transmitter The signal is then routed through A2 no filters Au wideband autorange and A5 FWA wideband detector Since the transmit signal from the return loss bridge has not been tested the termination test is also an A18 output check This signal is routed from A18 to A1 without going through the active output therefore the active output stage
15. 20 to O dBm 0 2 dB at 1004 Hz 60 to 10 dBm 1 5 HP h9h5A General Information Table 1 1 Specifications cont Flatness Total Distortion Receiver Frequency Range Resolution Accuracy Receiver Level Range Resolution Detector TE tT a i TETRA nippy RCH AS t 20 Hz 200 Hz 15 kHz 85 kHz 110 kHz Flatness is not specified below 200 Hz when using the 135 ohm termination 100 Hz to 3 kHz gt 50 dB down from fundamental measured in 3 dB bandwidth up to 12 kHz for signal levels 40 dBm to 10 dBm 3 kHz to 20 kHz gt 10 dB down from fundamental measured in 3 dB bandwidth up to 80 kHz for signal levels 40 dBm to 10 dBm 20 kHz to 110 kHz gt 40 dB down from fundamental measured in 3 dB bandwidth up to 440 kHz for signal levels 30 dBm to 10 dBm 20 Hz to 110 kHz 1 Hz from 20 Hz to 9999 Hz 10 Hz from 10 kHz to 110 kHz for signal levels gt 50 dBm at gt 20 dB signal to noise ratio 1 Hz from 20 Hz to 9999 Hz 10 Hz from 10 kHz to 110 kHz 60 to 13 dBm aod Tull wave average 1 6 HP 4OLSA General Information Table 1 1 Specifications cont Accuracy in dB 50 dBm to 13 dBm 20 Hz 200Hz 15 kHz 110 kHz 60 dBm to 50 dBm 20 Hz 200 Hz 15 kHz 110 kHz 1004 Hz holding tone accuracy is 0 1 4B from 20 to 0 dBm accuracy is not specified below 200 Hz when using the 135 ohm termination Filters Available 60 Hz highpass 10 kHz
16. At data transmission greater then 2400 bits per second over a voice channel without proper delay compensation the data bits tend to smear out in time and overlap each other causing inter symbol interference which produces errors An ideal circuit which has a linear phase shift characteristic will produce a straight line slope a linear relationship between a change in frequency and a cooresponding change in phase as shown in Figure 4 15a The practical circuit is never ideal and will produce a nonlinear phase shift characteristic phase distor tion as shown in Figure 4 15b Conventional measurement techniques make it difficult to measure the phase charac teristic of a transmission system because a phase reference is difficult to es tablish at the receiving end of the circuit It is possible however to measure relative phase shift at the receiving end using the envelope delay measurement technique This technique makes it possible to measure the envelope delay distortion of a voice channel which provides a relative measure of the phase linearity or nonlinearity of the circuit Relating Phase Shift to Envelope Delay Amplitude modulating a low frequency sine wave fm onto a carrier frequency fc produces an amplitude modulated am signal as shown by waveforms a b and c in Figure 4 16 The envelope of the AM signal is the outline or shape of the peak excursions of the modulated signal as shown in waveform d of Figure 4 16
17. Changing the frequency is very similar to changing the level When the FREQuency hardkey is pressed the following selections appear 09 28 83 10 39 AH 7 CHANGE FREQUENCY een RCY LEVEL 13 0 dBm o oru ere 1004 Hz RCV FREQUENCY 1004 Hz _ ay 3004 Hz 2713 Hz Figure 3 6 Frequency Softkey Selections Notice that the LED next to the hardkey will illuminate when this key is active There are three ways of changing the frequency of the instrument They are the Data ENTRY keys the up down arrow keys or selection of one of the preprogrammed frequencies The procedure for each of these is discussed below DATA ENTRY Keys When making a specific entry first press the FREQuency hardkey the DATA ENTRY block will come up on the screen in inverse video with an acceptable entry range on the line above it Next press the appropriate keys on the keypad to make the frequency entry The entries will show up in the DATA ENTRY block To finalize your selection press the ENTER key Up Down Arrow Keys These are located right below the LEVEL FREQuency and VOLUME hardkeys on the front panel The up down arrow keys can single step up or down a value The amount of the step size is set in this menu by pressing the Step Size softkey 7 The choices available are 10 50 100 and 1000 Hz 3 9 HP OSA Operation Programmable Frequencies When the FREQuency hardkey is pressed the softkey selections shown in figure 3 6 appear
18. Data Level using the LEVEL hardkey Note All transmission measurements should be made at Data Level The Data Level for data circuits is a power of 13 dB below the Transmission Level Point TLP For exam ple if the TLP is 16 dB the data level would be 29 dBm Therefore an output level of 29 dBm would be ap plied in this case Adjust the transmit frequency to the reference frequency e g 180h Hz or the frequency of minimum delay using the FREQuency hardkey 3539 HP h9h5A Operation Note The transmitter of the HP h9h5A is automatically set to 180h Hz when the envelope delay menu is accessed T When the Repeat Test Set operator has completed step 6 continue to step 8 8 Observe the RCV LEVEL in dBm on the display For valid measurements this level must be greater than or equal to 40 dBm 9 Observe the delay reading on the display Arrows will be displayed until the reading stablilizes Press the DELAY ZERO softkey 3 This establishes a reference at the reference frequency This can be verified by noting the display under ZERO REFERENCE 10 If you want a zero reference for the received level press the LEVEL ZERO softkey 2 The level which you selected as the reference is displayed under ZERO REFERENCE on the lower portion of the display 11 Notify the repeat test set operator to begin sending the agreed upon test frequencies 12 At each test frequency observe the relative delay in microseconds If th
19. It is good in terms of parity and framing but it is the incorrect response Direction of Test Either Problem Channel Either Additional Comments In this case the master has requested the slave to enter a measurement mode and the slave did not respond correctly Slave Fails To Execute Command H 06 When During link up or re link only Pilot Tone Yes Data Yes Direction of Test Either Problem Channel Communications Channel Additional Comments This error message occurs if the master receives no response from the initial inquiry sent to the slave Slave Looped Back H 07 When After link up Pilot Tone Yes Data Slave is in loopback mode Direction of Test Either Problem Channel No Additional Comments This error occurs when the master requests the slave to perform a measurement which is beyond its capabilities The slave will automatically go into loopback mode This occurs when interfacing with an HP 4943A or an HP h9hhA because of their limited measurement capability Applicable only if using an HP 4943A or an HP h9llhA 3 70 HP h9h5A Operation No Data Received From Slave H 09 When After link up Pilot Tone Yes Data No Direction of Test M S only Problem Channel Communications Channel Additional Comments In this case the master unit is expecting a response from the slave but it is only receiving the pilot tone Receiver Level Ou
20. Mode self check Segment self check Nonstop Check end Fail mode Fail end Calibrate SPECIAL DISPLAYS COMMANDS SPD SOFT KEY STATES Special displays hardkey These mnemonics will place the softkeys If an invalid state is specified state 0 is se numeric ASCII character These mnemonics should only be used to program retrofitable op lected into state s no no no no no no no no no no no where s is one tions since mnemonics to program everything else have been provided SK1 s S 2 s SK3 s SKh s SK5 s SK6 s SK7 s SK8 s SWEEP SET UP SW2 SW3 SWL SW5 SW6 Program softkey 1 to Program softkey 2 to Program softkey 3 to Program softkey 4 to Program softkey 5 to Program softkey 6 to Program softkey 7 to Program softkey 8 to Single sweep Continuous sweep Step rate 3 second Step rate l second Step rate 3 second 8 23 state state state state state state state state t U t hh d tA ih Yes Yes Yes Yes Yes Yes Yes Yes no no no no HP 4945A I O Module Codes Mnemonic Function Data Entry SWEEP SESTUP con t SW7 lt freq gt Set lower limit yes SW8 lt freg gt Set upper limit yes SW9 step gt Enter step size yes REAL TIME CLOCK Note This command will be executed without sending the EXC command since this is not measurement data No ENDST data type will be returned for the same reason TIM Read real tim
21. Not present TRMT RCV HP IB ADDRESSING The HP IB address is programmable from the front panel via the I O Port Set Up menu The default address is 10 To change the HP IB address use the following procedure Press SET UP I O PORT SET UP Press HP IB Address key and enter the desired address using data entry keys and then press ENTER key 5 7 HP 49454A HP IB Operation HP IB DEVICE FUNCTIONS The HP 18162A Interface has the following HP IB device capabilities which are com patible with IEEE Standard 488 1978 AHl Acceptor handshake SHi Source handshake CO No controller capability Lh Listen and unlisten if talk addressed T5 Full talker capability SRL serial poll capability RLi Full remote local capability PRI Complete parallel poll ability DCT Full device clear implementation DTO No device trigger capability 5 8 HP 4945A HP IB Operation MESSAGE DEFINITIONS Information is transferred on the HP IB from one device to one or more other devices in quantities called messages Some messages consist of two basic parts an ad dress portion and an information portion Others are general messages to all devices There are also messages which are referred to as meta messages The HP IB bus messages and module responses are listed and defined in table 5 2 The HP 4945A response to the message if any is described after each definition Note A meta message is not a program code or an HP IB com
22. Note The values may be different To change the frequency press the cooresponding softkey The values shown that correspond to softkeys 1 6 can be programmed as follows e Press softkey 8 which is labelled PROGRAM FREQUENCIES Notice that each of the frequencies is in parentheses e To change any of the values press the corresponding softkey Now use the data entry keys or the up down arrow keys to change it to the desired value Volume To control the speaker volume or the keyboard beep press the VOLUME hardkey The following selections will appear YOLUNE AE OFF HONITOR RECEIVE KBD BEEP 3 ON HESSAGE CKT NOISE dBrn 4 m RCV TERN i es mn as a nel nel eL non incre T dBm soo 8 TERMINATION 600 Figure 3 7 Volume Softkey Selections 3 10 HP h9h5A Operation Notice that the LED next to the hardkey will illuminate when this key is active Use softkey fl to turn the VOLUME ONE The volume range is from O to 6 with 6 being the loudest The level can be changed by using either the up down arrow keys or the DATA ENTRY keys Softkey 2 MONITOR selects whether the speaker is connected to the receiver or the transmitter Softkey 3 selects whether the keyboard beep is ON or OFF This does not affect warning beeps Changing Parameters Located Inside a Menu thresholds timers etc Any parameter which has the option of being changed will be inside parentheses If the parameter has
23. STOPPED TIHE ELAPSED 0 HIN 0 SEC COUNT RATE ae 7SEC IHPULSE NOISE Per LOW 68 dBrn CNTS COUNT TIHE 2 dBrn ITS C1 HIN 76 dBrn Sith be A IMPULSE LOU PHASE HITS 20 DEG E NTS 68 dBrn GAIN HITS 10 dB NS ao DROPOUTS 12 dB CNTS STEP SIZE Pane 4 dB NOISE U TONE dBrn C HESSAGE FILTER IN IRCV TERM 004 H 004 Hz BR 13 0 dBm 13 0 dBm Figure 3 16 The Transients Measurement Menu 1 This softkey starts and stops the timer on the transients measurement It tog gles between STOPPED and RUNNING HP 4945A Operation 2 This softkey sets the count rate for transient measurements It cycles through 7 8 and 100 counts per second 3 This softkey sets the timer for the transient measurement The range is pro grammable from 0 nonstop to 9999 minutes 4 This softkey sets the LOW threshold for impulse noise The range is programmable from 30 to 110 dBrn 5 This softkey sets the step size between the LOW to MID and MID to HIGH impulse noises thresholds It cycles through 2 3 4 5 and 6 dB 6 This softkey sets the phase hits threshold It cycles through 5 10 15 20 25 30 35 hO and 45 degrees T This key sets the gain hits threshold It cycles through 2 3 h 5 6 7 8 9 and 10 dB 8 This softkey accesses the noise filters menu For further explanation of this menu refer to the NOISE measurement section The noise filter selected affects the impulse noice measurement o
24. This appendix contains procedures to verify the operation of the HP LOUSA and can be used as an incoming inspection check The verification is divided into two procedures Power On Self Check and Diagnostics The Power On Self Check is automatically performed when the instrument is first turned on The Diagnostic tests can manually be run after that POWER ON SELF CHECK At power on the HP 4945A executes a series of self tests on the digital and analog circuits Error codes are displayed in the event of a hardware failure The instrument also beeps and lights the front panel LEDs to indicate the passage of some digital tests and to serve as an indication in case the display hardware is not functional Power on LED and Beep Sequence 1 A10 CRi LED on 2 Seven front panel LEDS all come on briefly then flash and go off These LEDs are located next to VOLUME LEVEL FREQ TRMT RCV RCV TRMT and HOLD 3 All passes VOLUME LED on and 1 beep h A12 passes LEVEL LED and and 2 beeps 5 A13 passes FREQ LED on and 3 beeps 6 VOLUME LEVEL FREQ LED off 7 A10 CR1 LED off 8 TRMT RCV LED on 9 A10 CR1 LED flashes 10 Display HP 4945A Operating Verification Error Codes Power on self check errors are displayed as they occur The test program discovers and displays as many errors as possible before arriving at a point where further testing is pointless If a key is pressed when the test program has stopped the ins
25. Warning message Highest priority End of set 8 7 HP 4945A I O Module Codes INTERMODULATION DISTORTION con t Four tone noise corrected RCVST 2 NCFMS 1 NCFSD DB SCDPR DB NCFTD DB THDPR DB AVGLV DBM STLVL DBM WARNG KX ENDST 0 Two tone RCVST 3 NCFMS 0 NCESD DB SCDPR DB NOCETD DB THDPR DB AVGLV DBM STLVL 2 DBM WARNG XX ENDST 0 No tones received RCVST NCFMS X NCFSD DB SCDPR DB NCETD DB THDER DB AVGLV DBM STLVL DBM WARNG XX ENDST 0 JITTER Receive status four tones Noise correction factor message corrected Noise correction factor second order Second product Noise correction factor third order Third product Average level Status field level Warning message Highest priority End of set Receive status two tones Noise correction factor message not corrected Noise correction factor second order Second product Noise correction factor third order Third product Average level Status fieid level Warning message Highest priority End of set Receive status no tones Noise correction factor message Noise correction factor second order Second product Noise correction factor third order lhird product Average level Status field level Warning message Highest priority End of set 20 300 Hz Amplitude and phase AMPJH PK PHJHI DEG STLVL D
26. code 203 Al2 U300 Bank 1 ROM 2000 5FFF bad rev code 204 A12 ULOO Bank 2 ROM 2000 SFFF bad rev code 205 Al2 U102 Bank 2 ROM 2000 5FFF bad rev code 206 A12 U202 Bank 4 ROM 2000 SFFF bad rev code 207 Al2 U302 Bank 5 ROM 2000 5FFF bad rev code 208 A12 U1l04 Bank 6 ROM 2000 5FFF bad rev code 209 12 U204 Bank 7 ROM 2000 5FFF bad rev code 21i 10 U607 Receiver ROM 1 EO00 FFFF bad rev code 212 A10 U507 Receiver ROM 2 COOO DFFF bad rev code 213 A10 UL407 Receiver ROM 3 A000 BFFF bad rev code 214 A10 U308 Receiver ROM 4 8000 OFFF bad rev code 215 A10 U307 Receiver ROM 5 6000 7FFF bad rev code 216 A10 U306 Receiver ROM 6 4000 5FFF bad rev code 217 A10 U305 Receiver ROM 7 2000 3FFF bad rev code 218 A9 U4LOO Transients board ROM bad rev code 19 Receiver software overall bad rev code A 3 HP h9h5A Operating Verification 300 301 30h 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 400 401 402 403 you 500 501 502 503 504 205 600 604 605 606 607 609 610 611 612 100 A13 U206 Display A11 UhOh System STACK RAM 0000 OTFF R W error A10 U503 System SHARED RAM 0800 0FFF R W error A12 U500 System RAM EO00 ETFF R W error A12 U402 System RAM E800 EFFF R W error A10 U503 Receiver SHARED RAM 0000 07FF R W error A10 Uh05 Receiver RAM 0800 OFFF
27. mand It is only intended as a tool to translate a program written as an algorithm into the controller s code Table 5 2 HP IB Messages and HP 49454 Responses Definition and Response The actual information bytes sent from a talker to one or more listeners The information or data can be in numeric form or a string of characters The HP L9h5A accepts data messages when addressed to listen The HP 4Ok5A can send data messages when addressed to talk Trigger Causes the listening device s to perform a device dependent action The HP 495A ignores this message Clear Causes devices to return to a pre defined device dependent state 2 9 HP 49454 HP IB Operation Table 5 2 HP IB Messages and HP 49454A Responses con t Message Selected device clear conditions Menu RCV TMT RCV IMP Hold Coils SF Skip Voice Limit Master Slave Talk Battery Self Check Noise Sweep Measurement Jitter Return Loss EDD Transients Level keys Freq Keys Volume Definition and Response SDC commmands returns the HP 4oOh5A to the following Test Select TERM 600 OFF OFF OFF NORMAL OFF Master to Slave mode OFF Full Mode 1 Segment 1 stop on end check Noise with tone C MSG Fiiter IN 60 Hz Filter OUT Stopped Single from 204 Hz to 3904 Hz Step 100 Hz Rate Fast Level Freq Quiet Termination 1004 Hz 20 300 Hz Amplit
28. 1 3 4 8192 Hz from A15 wide 8192 1 4 5 32768 Hz from A15 wide 3276 1 0 5 6 65536 Hz from A15 wide 6553 1 0 6 7 thru 16 not used A signal from A15 sets the transmitter to the frequency for the particular segment The signal level is 775 Vrms The signal is input to the receiver at the Al multiplexer The frequency is read at the A8 wideband channel for paths 1 and 3 through 6 The narrowband channel is used for path 2 A 13 HP hOh5A Operating Verification Diagnostics Mode T MODE 7 Transmitter Single Tone Check A4 AB Aid A15 This mode connects the self test signal output from A15 directly to the Ah input multiplexer A 32 Hz 775 Vrms sine wave is transmitted and measured by the A8 frequency counter The bits in the transmitter frequency counter are changed one at a time to produce higher subsequent frequencies Any errors in the fractional N synthesizer show up as frequency offsets during the test The frequencies change in the order listed below Following is a summary of the Mode 7 tests Data Frequency and Results Segment Displayed Should Be i 1 P ena 2 33 0 3 34 0 n 36 0 5 LO 0 6 48 0 7 64 0 8 128 0 9 256 0 10 512 0 11 1024 0 12 2048 0 13 4096 0 ih 8192 0 15 16384 display 1638 0 1 16 32768 display 3276 1 0 The transmitter transmits frequencies sequentially in the order listed above The signal level from A15 is 775 Vrms The signal i
29. 1 5 dB True rms INTERMODULATION DISTORTION MEASUREMENT Transmitter Signal Spectrum Level Range Receiver Signal Level Range Resolution Accuracy Filters Distortion Range four tone non linear distortion two tone noise check 40 dBm to O dBm not specified at 135 ohms 40 dBm to O dBm i dB 1 dB Second order centered at 520 Hz and 2240 Hz Third order centered at 1900 Hz 10 to 55 dB not specified at 135 ohms PEAK TO AVERAGE RATIO MEASUREMENT P AR Transmitter Signal Spectrum Level Range Level Resolution meets Bell System PUB 41009 specifications and IEEE Std 743 1984 40 to O dBm 0 1 dB 1 9 HP 4945A General Information Tablei 1 Specifications cont Receiver Signal Level Range P AR Range Accuracy Resolution hO to 0 dBm O to 120 units 2 P AR units over range of 40 to 110 units 4 P AR units elsewhere 1 P AR unit PHASE AND AMPLITUDE JITTER MEASUREMENTS Transmitter Frequency Receiver Level Range Bandwidths Phase Jitter Amplitude Jitter Outputs TRANSIENTS MEASUREMENT Transmitter Frequency Receiver Holding Tone Count Rate Count Range Timer 1004 Hz fixed 40 to 10 dBm 34 dBm to 10 dBm at 135 ohms 20 to 300 Hz 4 to 20 Hz and h to 300 Hz 0 0 to 30 0 degrees peak to peak or 5 percent of reading plus or 0 2 degrees peak to peak 0 0 to 30 0 percent peak to peak or 5 percen
30. 4945A HP IB Operation USING THE HP 4945A AS AN HP 4944A OR AN HP 4943A To enter this mode all that it is necessary to do is to send one or more of the HP OLLA mnemonics The mode of operation and the instrument set up will not change A device clear command must be sent to the HPIB module prior to or just after en tering HP 4944A mode to put the intrument in a known state to remove any data from the output queue and to reset the status register This mode will be exited if a HP h0h5A mnemonic is received if the selected device clear is received or if a semicolon is received As the HP hOhhA does not respond to selected device clear the HP 4Q4LA mnemonics do not contain semicolons and are a different format than HP H9lh5A mnemonics this transition should not occur unless there is an an error in the program When the HP hOhhA mode is exited one of the clear comands device clear or selected device clear must be sent to reset the status register and to clear the output queue of any data CAUTION It is very important to send one of the clear commands when entering the HP hOhhA mode If the HP h9h5A is making a measurement that the HP 4G4LLA cannot do or is making a measurement outside the frecuency range of the HP 4Q44A the bus may lockup when the controller tries to input data In this mode measurement data is returned from the HP 4945A in the same format as the HP 4Q44UA returns it In addition to HP 4944A mnemonics another mnemonic
31. 6 1 199 20dB 10dB 10dB 10000 200 T 1199 hodB OaB 20dB 20000 200 8 1199 30dB 10dB 20dB 20000 200 9 1199 504B OdB 304B 30000 200 10 1199 hOdB 10dB 30dB 30000 200 11 1199 60dB OdB hOdB 40000 200 1 1199 50dB 10dB 40dB 40000 200 13 1199 TOdB OdB 50dB 50000 5000 14 1199 60dB 104B 504B 50000 5000 15 1199 BoaB OdB 604B 60000 2000 5000 16 1199 704B 10aB 604B 60000 2000 5000 HP 4945A Operating Verification Diagnostics Mode 6 MODE 6 Frequency Counter and Crystal Check A4 A8 A14 A15 This mode connects the self test signal ST16 from A15 directly to the Ah input multiplexer A 625 Hz 775 Vrms sine wave is transmitted and measured by the A8 frequency counter The transmitter is then driven in sequence by the following clock signals e 10 kHz clock derived from the 1 MHz system clock e The 16 kHz clock from All e The 131 kHz clock from All e The 16 kHz from Ail e The 131 kHz from a crystal on A1 The 524 kHz from the crystal on ALY e The 1 MHz from the crystal on All This helps to isolate bad oscillators as well as verifying AB operation Since the transmitter output is 1000 Hz with the 16 kHz clock it is measured in both narrowband and wideband channels Following is a summary of the Mode 6 tests Results Displayed Should Be Data Segment 625 Hz from A15 wide 2 1000 Hz from A15 narrow 1000 1 2 3 1000 Hz from A15 wide 1000
32. A15 A17 6 Frequency Counter and Crystal Check Ah A8 All A15 T Transmitter Single Tone Check Ah A8 All A15 8 Transmitter Multi Tone Check Ah A8 All A15 9 Transmitter Filter Sweep Ah A15 10 Transmitter Alternate Channel Check Ah A8 A15 11 Wideband Filter Calibration Al A2 Ah A12 A17 12 A2 Filter Sweeps A2 Ah A5 A17 13 A2 Filter Sweeps Continued A2 Au AS ALT 1h Al and A18 Check Al A2 Ah AS A17 A18 15 IMD Hardware Check A2 A3 Ah A5 Al7 A18 16 IMD Filter Calibration A2 A3 Ah A17 37 Jitter Digital and Phase Lock Loop Check Al A6 18 Jitter Calibration A6 19 Envelope Delay Hardware Check Ah A5 AT All ALT 20 Envelope Delay Calibration A1 A2 Ah AT A17 2i Transient Measurements Check Al A2 Ah A8 AO A17 22 A3 FSK Demodulation Check Al A2 A3 A1h A17 A 6 Condition CHECK END FAIL MODE FAIL END HON STOP When the test stops HP h9h5A Operating Verification Table A 2 Stop on Conditions Description Stops at the end of the selected test i e at the end of the selected mode or at the end of all modes when FULL is selected Stops at the end of the mode in which a failure has occurred This mode runs non stop if no error occurs Stops after running all the modes when a failure occurs Run the selected tests continually because of one of these conditions press START STOP to start the test over again Press START S
33. AR of the output signal of the system under test The P AR measurement is most sensitive to envelope delay distortion and is also affected by noise bandwidth reduction gain ripples nonlinearities such as compression and clipping and other impairments The P AR rating is an indication of the general transmissions quality of the voice band channel If the P AR signal were received entirely undistorted the P AR rating would be 100 while a circuit that causes a 10 percent reduction in the peak to average ratio has a P AR rating of 90 The P AR measurement provides little information about the nature of the fault con dition of any particular case However since P AR is a figure of merit for the channel it can be used as a benchmark for future reference After other measure ments are made and a channel is considered acceptable the P AR rating can be re corded for future reference In case of a suspected trouble on the channel P AR may be measured first and be compared to the benchmark P AR value Deviations in excess of or 4 P AR units from an initial P AR value provides sufficient reason to suspect that some channel characteristic has changed significantly The P AR rating can also be useful in trouble shooting on the DDD network where a number of connections are to be surveyed and full data recorded on only the worst connections experienced In private line circuits P AR can help to identify the Worst transmission direction near to far
34. HI Q AGC HI Q AGC HI Q HI Q TUNING FSK BPF FSK BPF FSK BPF Delay Delay Delay Delay Delay the system software does not set the AGC DAC U503 A 27 Path 10 10 10 10 10 HP 4OU5A Operating Verification Diagnostics Mode 20 MODE 20 Envelope Delay Calibration A1 A2 A4 A7 A17 Envelope delay calibration is software compensation for the HP 4945 s receiver and transmitter deviation from linear phase The deviation is measured by comparing the delay at 1804 Hz to the delays at frequencies from 200 to 840 Hz at 64 Hz intervals These values are stored in a table and used to correct envelope delay measurements taken at frequencies covered in the table Interpolation is used to calculate intermediate values The correction provides a delay flatness of 4 microseconds At frequencies above 840 Hz delay flatness is assumed not to be a problem The transmitter signal is routed from A17 to the Al multiplexer through A2 and Al wideband autorange and then to AT Following is a summary of the Mode 20 tests The results displayed are in microseconds Results Data Displayed Test Segment Should Be signal at A17TP2 Path 4 O TO 200 Hz 0O dBm 600 1 2 0 50 264 Hz 0 dBm 600 2 3 0 ho 328 Hz 0 dBm 600 3 0 30 392 Hz 0 dBm 600 4 5 0 30 456 Hz 0 dBm 600 5 6 O 20 520 Hz 0 dBm 600 6 7 0 20 584 Hz 0 dBm 600 7 l 8 0 20 648 Hz 0 dBm 600 8 9 0 10 712 Hz 0 dBm 600
35. M8 has been included in the set of mnemonics so that existing HP 943A programs can be altered to also operate the HP h9h5A The HP 4943A uses the code M7 for phase jit ter 20 300 Hz while the HP 494A uses MT for nonlinear distortion The HP 4945A interprets M8 code as phase jitter 20 300 Hz and returns the data in HP Hh9h3A format Replacing all occurrences of M7 with M8 in an HP 4943A program will allow it to run with the HP 49454A The codes CO and Cl self check have not been implemented and must be removed from any program which uses them before the program in question will run One important difference between the HP h9h5A and the HP HOLLA or HP h9h3A is that functions that are not remotely programmable on the HP 4OMMA HP h9h3A are program mable via HP IB on the HP 4O45A When the HP h9h5A executes a device clear these functions are reinitialized default values Understanding this difference is impor tant when using the device clear The following table is a summary of these differences VU D CN HP 4944A Function Power Set up switches Normal test dial talk Hold coils on off Talk battery on off Term bridge 600 ohms 900 ohms SF skip on off Normal test self check Transmitter level Impulse noise threshold Line monitor volume Analog output RCV TRMT switch HP 495A HP IB Operation HP 4945A DCL State no change Normal test Off Off Term 600 ohms Off Normal test 16 0 dBm 68 dB 3 receive monitor
36. Manual Changes supplement contact your nearest Hewlett Packard office To verify the latest version perform the SET UP and TURN ON procedure in Chapter III Then perform the following steps e Press CALIBRATE SELF CHECK softkey e Press TEST PATTERN softkey The software version code will be shown at the bottom of the CRT display DESCRIPTION The HP 4945A is a multifunction test set that is used to measure the quality of voice grade program and wideband data communications channels The instrument is designed for problem isolation on high speed data transmission circuits The instrument has mounting feet on the rear panel and the right side as well as on the bottom panel This allows the instrument to be set vertically or horizontally as required rack mounting option is also available The HP 4O4SA interfaces are RS 232C HP IB and HP IL The front panel contains a membrane switch type keyboard Measurement results are displayed on a nonglare CRT The HP 49Q45A incorporates master slave provisions for use on lh wire circuits Measurement control for both directions of transmission is at one end of the circuit At the control end is the master unit At the remotely controlled end is the slave unit All test results for both directions are displayed at the master unit Choice of the direction of test i e master to slave or slave to master is by switch selection at the master unit Once the slave unit is set up it can be left una
37. Rate Fast Measurement Level Frequency Quiet term 1004 Hz Jitter 20 300 Hz band Amplitude and Phase Return loss Measure All 2 wire Hybrid loss 00 0 Envelope delay Normal Transients Stopped 8 per sec 15 min 4 dB step 68 dB threshold 20 degrees 10 dB gain hit Ref imp 600 ohms 6 6 HP h9h5A HP IL Operation Table 6 1 HP IL Loop Messages and Module Responses con t Level softkeys Frequency softkeys Volume TRMT RCV switch SDC or DCL Remote enable REN Go To Local GTL Local Lockout LLO Not Remote Enable NRE Serial Poll Parallel Poll Configure PPC Parallel Poll Enable PPE Parallel Poll Disable PPD Parallel Poll PPU Parallel Poll Listen Address LAD Response Defaults 7 0 0 0 6 0 13 0 29 0 Defaults 304 LOL 1004 2804 3004 2713 Off Level 3 Monitor Receive Beep on TRMT RCV Resets the queues stops any measurement in process Mode of instrument goes to normal direct mode is exited Puts the HP 4945A into remote enabled state Puts the HP 445A into local state if listen addressed If Remote enabled puts the HP 4OL5A into lockout states Returns the HP h9h5A to local state no lockout Module sends its current status over the loop Puts module into a state where parallel poll response may be programmed If the last command was the parallel poll configure programs the parallel poll response If the
38. Set baud rate 9600 No parity Even parity Odd parity Mark parity Space parity Ralf duplex Full duplex 1 stop bit length 7 stop bits length 7 2 1 stop bit length 8 2 stop bits length 8 Amplitude jitter off Amplitude jitter on Phase jitter off Phase jitter on 20 300 Hz 3 300 Hz 3 20 Hz Measure a ll Level frequency 60 Hz filter out 60 Hz filter in 8 18 Data Entry no no no no no no no no no no no no no no no no no Mnemonic LEVEL LVO lt level gt LV1 LV2 LV3 LV4 LV5 LV6 LVT LV8 LVO LVA lt level gt LVB level LVC level LVD level LVE level MASTER SLAVE SET UP MSO MS1 MS2 MS3 NOISE FILTER COMMANDS NFO NFL NF2 NF3 NF Program level HP N9h5A I O Module Codes Function Data Entry Program transmitter level Level 1 Level 2 Level 3 Level 4 Level 5 Quiet termination Step size 1 Step size 3 Step size 1 Program level Program level Program level Program level Wiki hb RS M S mode off Master amp Master to Slave Master amp Slave to Master Slave C message filter 3 KHz flat 15 KHz flat Program 50 Kbit yes no no no no no no no no yes yes yes yes yes ho no no no no no no no no If one of the noise filter commands is selected when starting to make transient measurements the transient measurement will be replaced with noise with tone To avoid
39. Signal Frequency Spectrulhaeesriesaswdsuw kc wXPE AS seek ad 4 23 Relating Phase Shift to Envelope Delay cccseccceececeres 4 24 Envelope Delay Measurement ccc cee eee ee hh hh erences 4 25 viii Figure 4 20 4 21 4 22 h 23 5 1 5 2 6 1 Tols HP LOLSA List of Illustrations LIST OF ILLUSTRATIONS con t Page Intermodulating Distortion Signal Frequency Spectrum lassus 4 27 P AR Transmit Signal Frequency Spectrum een 4 30 P AR Transmit Signal Envelope ocean 4 30 Filter Shapes for ERL SRL Low and SRL High ns 4 34 HP 18162A Interface Installation ccecccccccccecccccccccece 5 2 Interface Connections and Bus Structure cn 5 4 HP 161654 Interface Installation an can 6 2 HP 18163A Interface Installationoloilo sg ip a vaa elder 7 1 ix HP hol5A List of Tables Table 2 1 3 1 u 1 4 2 4 3 ued 5 1 5 2 6 1 8 1 LIST OF TABLES Page Sp cifications dern an b rex rbxke km rss aachen 1 h Line Fuse Port NumbOeTS eee ee as po ac Eon RESET bisher pe Circuit Control Settings bor RO RES CERCA VOIE UL at og edite 3 20 Filter Noise Bang au eate ot Ben aad Sock ame eda dd af que 4 5 Transient Phenomena Summary ru eoe ba gabe Do euet reine 4 16 Measurement D fini tions css vv Gea eee eee MASSE re Raed 4 16 Harmonics and Intermodulation Products of a Multiple Frequency Signal TI and FD tw tare ha wish bbe Ea we ea EO ware 4 28 General Interface Management Lines
40. Test signal at A17TP2 1380 Hz O dBm 600 860 Hz O dBm 600 2940 Hz 0 dBm 600 3280 Hz O aBm 600 490 Hz 0 dBm 600 520 Hz O dBm 600 550 Hz 0 dBm 600 520 Hz 30 dBm 600 1900 Hz 0 dBm 600 1900 Hz 0 dBm 600 2240 Hz 0 dBm 600 2240 Hz O dBm 600 Filter Notch Notch Notch Notch BPF BPF BPF Mixer Mixer Mixer Mixer Mixer No detect detect at 1380 Hz No detect detect at 860 Hz For Data Segments 13 and 14 LO ho FP Q RO Hn Gk no tones detected 1380 Hz tone detected 860 Hz tone detected both tones detected Path 10 10 HP h9h5A Operating Verification Diagnostics Mode 16 MODE 16 IMD Filter Calibration A2 A3 A4 A17 This mode tests the gain constant of the three bandpass filters used in IMD and the noise floor of each filter There is actually only one bandpass filter which is preceeded by the A3 mixer The mixer can generate a 520 Hz component from a 1990 or 2240 Hz signal The resultant 220 Hz component has an amplitude proportional to the 1900 or 2240 Hz signal depending on the mixing signal Thus there are three different passband frequencies the noise floors of each filter are not equal For Data Segments 1 3 The transmit signal is sent from A17 to the A input multiplexer through A2 on the IMDI line to A3 The signal level is measured with the wideband autorange and the rms detector All level measurements are made relative to the level measure
41. UP DOWN arrow is replaced with 9 9E8 When these numbers replace the arrows the length of the string is increased by four to Six characters so that string dimensions at the beginning of the user progams should reflect the possibility of receiving these values String dimenions of 32 characters will handle any strings sourced by the HP LOLSA The last characters of each string are a carriage return and a linefeed The car riage return linefeed pair is used to terminate an enter statement Each measurement returns a number of these data strings To determine when there is amp complete set of data for the measurement in question the end of set data type is used with dummy data The end of set string is ENDST 0 To start another mea surement the EXC command should now be sent as no more data should be forthcoming HP h9h5A I O Module Codes Table 8 1 list the measurements and the header that preceeds that measurement listed in the table are the measurement units Table 8 1 Measurement Results and Headers MEASUREMENT RESULT Frequency receiver status Level receiver status Noise Noise to ground Noise with tone Signal to noise ratio Peak to average ratio Sine wave return loss Relative level Delay Second product Third product Frequency high receive status No self check mode in execution Transients drop out count Transients gain hit count Transients phase hit count Impulse noise high impulse noise mi
42. a pre determined set of choices then when the softkey is pressed it will cycle through the selections If there is a range that exists for that parameter then when the softkey is pressed a data entry block will appear on the screen You can now make either a numerical entry using the keypad or use the up down arrow keys to change the parameter To end the entry mode either press the ENTER key or any key other than the DATA ENTRY keys POWER ON SELF CHECK The HP 4945A performs an automatic self check on power on During power on a series of beeps will indicate that the self check is in progress In addition to the beeps the LED indicators located on the front panel will flash The power on self check verifies the performance of the major circuitry In the event of a hardware failure an error code s will be displayed on the screen Er ror codes are listed and explained in the HP h9l5A Service Manual in Section VIII If power on self echck errors are displayed it may Still be possible to continue using the instrument by pressing any key The cause of the errors however should be corrected as soon as possible oak HP h9h5A Operation SET UP AND TURN ON PROCEDURE General i Connect the power cord to the receptacle on the rear panel of the instrument 2 Press the LINE button in to turn the instrument on A series of beeps at power on indicates that the self check is in progress Do not operate the instrument inside the car
43. affected by the jitter bandwidth selected Note If both amplitude and phase jitter are on this will not be a stable output 3 CARRIER Output The CARRIER output provides a square wave output signal whose frequency corresponds to the received carrier signal 4 EXTERNAL REFERENCE This is active only in 2 wire return loss The HP h9hs5A has the capability of using an external reference in place of the standard 600 ohms or 900 chms which are in series with a 2 16 uF capacitor This option is selected using the softkeys in the Return Loss measurement set up menu 5 Ac power line connector 6 Fuse T Voltage selector switch 115 or 230 VAC Monitor Jack External headphones or speaker can be connected to this jack When the headphone jack is inserted the internal speaker is disabled a 3 4 HP l9h5A Operation CRT DISPLAY FUNCTIONS The HP h9h5A display screen is divided into functional areas that allow for quick and accurate interpretation of the displayed data Figure 3 3 identifies these functional areas 10 41 aH CALIBRATE SELF CHECK TT ee cea SET UP TRHT IMPEDANCE ee RCYR IMPEDANCE 00 ITO MALUS RCVR TERN BRDS SET U SF SKIP SET UP VOICE BAND LIHIT OEE 176 PORT TRHT HOLD COIL ANE SET UP 6 REYR HOLD COIL eimi DATE TINE SET UP Til COFF HASTER E TO SLAVE wa d Ed RCY TERHI re 13 0 dBm 1004 Hz 13 0 dBm Figure 3 3 Display Features Area i This
44. being switched in 10 dB steps The receiver input at the Al multiplexer is set to ground as well as the input to the Al narrowband autorange amplifier When running the whole test paths 1 through 8 evaluate the true settling time of the amplifier by waiting 500 msec between gain switching Segments 9 through 16 use the programmed settling times to ensure that the times in paths 1 through 8 are correct When running a particular segment the receiver enters a loop within the path that repeatediy switches the gain between two states Mode 48 DC Offset Settling Time wideband This mode checks the de offset settling times in the wideband autorange amplifier when the gain is being switched in 10 dB steps The receiver input at the A1 multiplexer is set to ground as well as the input to the Ah wideband autorange amplifier When running the whole test paths 1 through 8 evaluate the true settling time of the amplifier by waiting 500 msec between gain switching Segments 9 through 16 use the programmed settling times to ensure that the times in paths 1 through 8 are correct When running a particular segment the receiver enters a loop within the path that repeatedly switches the gain between two states HP LOUSA Operating Verification Diagnostics Mode 49 Mode 49 Filter Path Checks This performance verification mode uses the receiver as a voltmeter and uses a different filter for each path The signal level measured is referred to t
45. cn RE TO a ee Transients exev se FUP TP Envelope Delay Distortion eere eei Intermodulation Distortion Measurement FECTED ols oi die bee db Bees dix oeque Pie ee e ada or E Res Ue pate us alla ato mapas videt bnew es P AR Peak to Average Ratio Measurement Returm TOSS ces oS theca ay create Wes Gases QA qeu Pre dire ie ak ig at wen gine Catton Onde at Ge eck How to Dump the Display to a Printer Using the Display Messages 2e bucal oia sug qas iii erosoa ere 0 ae oa 9 meee of eo ve vo ve hw ete ota 6 9 ae re eh ee 7 ew a t ete t Output eee 3 7 5 5 HP h9h5A Table of Contents Page P 1 LI E s 1 a a E gt t 1 d CO oO CO CO PO r9 i2 F3 F3 FR H Ra RS RS PRE p3 pa S e aoe 9 eee tee 354 ae ov we eae 1 i WM FO PO BS EX Eu RS RS LI TO PO P9 PO fO nO PO fO fO A t LI E 1 gt F E i b P t a t CJ Go CO 1 a t 1 LH E 1 t 1 1 ONE ue PALO Reo FI eoe eens oo MO Ov Q MUM Fr AH r9 FS Li gt s H n gt H 1 t t Hardkeys 1 V9 G9 WW WWW WW GJ GO WWW CO 1 Bo erp a tee HP LOLSA Table
46. dB the Data Level would be 29 dBm Therefore an output level of 29 dBm would be applied in this case When the Repeat Test Set operator has completed step 6 continue to step 7 Observe the RCV LEVEL in dBm on the display For valid measurements this level must be greater than or equal to 40 dBm Adjust the transmit frequency to the reference frequency e g 1804 Hz or the frequency of minimum delay using the FREQuency hardkey 2d HP h9h5A Operation 10 Lia 12 Note The transmitter of the HP 4945A is automatically set to 1804 Hz when the envelope delay menu is accessed Note If SF signaling units are used in the network under test SF SKIP should be ON refer to the Set Up Procedure Observe the delay reading on the display Arrows vill be displayed until the reading stabilizes Press the DELAY ZERO softkey 3 This establishes a zero reference at the reference frequency This can be verified by noting the display under ZERO REFERENCE If you want a zero reference for the received level press the LEVEL ZERO softkey 2 The level which you selected as the reference is displayed under ZERO REFERENCE on the lower portion of the display Iransmit the desired test frequencies using the FREQuency hardkey or the pro grammable sweep capability At each test frequency observe the relative delay in microseconds If the readings vary take the average General Instructions Return Reference Re
47. happen when the unit at the far end is set to MASTER This is called capturing the slave This avoids the need to have a person at the Slave site You will not be able to capture an instrument that is in calibration self check or 2 wire return loss mode Note On the Master unit all keys except the MASTER SLAVE softkey on the front panel will be locked out during initial link up Note Ihe FSK signal level will track the measurement signal level down to 29 dBm Below that the FSK signal level will remain at 29 dBm regardless of the measurement signal level which is set Softkey fT toggles between MASTER TO SLAVE and SLAVE TO MASTER This is setting the direction of test as shown in figure 3 25 You should set this to the desired testing configuration Notice that changing this setting causes the instruments to re link Now you can proceed through the normal operating sections This manual is organized so that any additional notes pertaining to Master Slave operation are included at the end of each section Basically you operate the instrument just as you would in normal operation Note If you are using the HP 4O45A with either an HP h9l3A or an HP LOLLA then refer to the next Section for addi tional information 3 65 HP 4OUSA Operation MASTER SLAVE WHEN USING AN HP 4943A OR AN HP 4944A WITH THE HP 4945A Why is it Different The HP 4943A and HP h9hhA are the original Hewlett Packard instruments d
48. have been sent Otherwise the mnemonic is ignored 8 14 HP Mnemonic CLOCK SET UP CLO cL1 CL CL3 CL CL5 CL6 CLT CL8 year month day hour minute DATA ENTRY DAT num exp gt DIAL HOLD SET UP DHO DH1 DH2 DH3 DH DH5 DH6 DH7 ENVELOPE DELAY EDO EDI ED2 ED3 4945A MNEMONICS Function Set Set set Set Set AM PM 12 hour 24 hour year month day hours minutes Sends the numeric expression the HP H9h5A and follows it with an enter code Transmitter hold off Transmitter hold on Reciever hold off Reciever hold on Dial talk off Dial talk on Talk bat off Talk bat on E D normal set E D repeat E D with freq data E D without freq data HP LOUSA I O Module Codes Data Entry yes yes yes yes yes no no no yes no no no no no no no no no no no no HP U49454 I O Module Codes Mnemonic Function Data Entry EXECUTE EXC Begin measurement no This command will cause the HP 4945A to make a measurement and pass the data back to the controller It is not necessary to send this command to cause execution of a mnemonic the semicolon or linefeed will do that Some commands such as OI or TIM cause data that is not measurement data to be passed back to the controller Commands of this type do not require that EXC command be sent for them to be executed and do not return the end of set data type EN
49. install interface with power on Operating power must be off INSTALLATION WARNING The HP 4O4SA operating power must be off before in stalling the interface Damage to the instrument or to the HP 18163A can result The HP 18163A Interface connects to one of the I O slots on the HP u9h5A rear pan el An RS 232C cable connects to the female D connector HP 18163A HP 4945A RS 232 CABLE Figure 7 1 HP 181634 Interface Installation T t HP LOUSA RS 232C Operation The signal lines and the connector pins used by the interface are listed below EIA Pin Signal Code Direction Protective Ground Transmitted Data TX To External Device From External Device Received Data RX Request to Send RTS To External Device From External Device Clear to Send CTS Data Set Ready DSR From External Device Signal Ground From External Device Received line detect CD Data Terminal Ready DTR To External Device The interface receives its power from the HP h9h5A No external power source is required Several RS 232C functions must be defined so that the interface is compatible with the system The following functions can be set from the front panel of the HP 4945A via the I O PORT SET UP menu Bit Rates 50 75 110 150 300 600 1200 h800 9600 Duplex Half Full Modem Handshake ON OFF Software Handshake ENQ ACK XON XOFF DC1 DC3 NONE
50. line is dedicated to the date and time In the 2l hour clock mode the AM PM indication is not displayed Area 2 This area contains three lines The middle line labels the menu you are in and designates the softkeys to specific functions The other two lines are designated for informational messages Area 3 This area is reserved for the measurement data or set up information Area 4 This area contains three lines The types of messages that may be found here are data entry messages power on messages calibrate self check messages Area 5 Referring to this area will quickly tell you the transmitter and receiver configuration 3 5 HP 4945A Operation Area 6 This area defines the functions of each of the softkeys Since the HP 4945A is menu driven each of these softkeys are redefined when a new selection is made 3 6 HP h9h5A Operation OPERATING THE HP 4945A Figure 3 4 Data Entry Level Frequency Volume Hardkeys Level To change the transmitter s level press the LEVEL hardkey The following selec tions will appear 09 28 83 10 38 AM CHANGE LEVEL 2 RCV LEVEL 13 0 dBm RCY FREQUENCY 1004 Hz 4 QUIET 6 TERMINATION STEP SIZE EENE Kr T T Ne mI 3 0 dBm of PROGRAH 13 0 dBm 600 LEVELS 8 Figure 3 5 Level Softkey Selections ory HP 4945A Operation Notice that the LED next to the hardkey will illuminate when this key is active There a
51. messages traveling from one device to the next around the loop in only one direction HP OSA HP IL Operation INSTALLATION The HP 18165A Interface connects to one of the I O slots on the HP 49454 rear panel The HP IL cables connect to the other HP 18165A connectors as shown in Figure 6 1 WARNING The HP 4955A operating power must be off Do not install interface with power on The interface receives its power from the HP 4O45A No external power source is required HP 4945A HP 18165A 7 int Ant enm T en ar aa ratae a A r a Am ana RE a rear ran Figure 6 1 HP 18165A Interface Installation 6 2 HP h9h5A HP IL Operation SELECT CODE address The interface select code is used in programming to designate the interface to which output is sent by the controller The default select code for the HP IL interface is 1 two devices in the loop When more than two devices are connected in the loop the select code of the interface changes with its position in the loop e g the fourth device in a loop is select code 4 etc COMMUNICATION CAPABILITY Loop functions provide the capability for a loop device to send receive and process messages if the device has the functional capability to do so Some of the common functions are described below Handshake A technique used by devices to synchronize information transfer Listener A device with listen capability that is listener active As such
52. now quiet terminated Noise With Tone Press the NOISE WITH TONE softkey 2 The transmitter is now transmitting a 1004 Hz holding tone Adjust the output level to the Data Level using the LEVEL hardkey refer to Data Level above General instructions Receiver Ls 2 Press the TEST SELECT hardkey Press the NOISE softkey 2 The current filter selected is displayed on the lower portion of the screen If you want to change to another filter press the SELECT FILTER softkey 8 and select the desired weighting or press the RETURN TO NOISE softkey 8 Message Circuit Noise Press the MESSAGE CKT NOISE softkey 4 The reading in dBrn will be displayed Single Frequency Interference While performing a message circuit noise measurement a Single frequency inter ference check can be done Press the VOLUME hardkey Press the VOLUME softkey 1 until ON appears in parentheses HP 4OLSA Operation 10 Ils Adjust the volume level by using either the up down arrow keys or the DATA ENTRY keys Press the MONITOR softkey 2 until RECEIVE appears in parentheses Listen for any predominant tone which will indicate a potential single frequency inter ference problem A LEVEL FREQUENCY measurement can be made Don t change the transmitter keep it quiet terminated to further analyze the tone Press VOLUME hardkey to end the entries Signal to Noise Ratio Press the SIGNAL TO NOISE softkey 3
53. or far to near such that measurement of the parameters in the worst direction can be completed first since it is more probably that any transmission impairment will be in that direction 4 29 HP 4945A Measurement Principles FREQUENCY 140 625 390 625 640 625 890 625 1140 625 1390 625 1640 625 1890 625 2140 625 2390 625 2640 625 2890 625 3140 626 3390 625 3640 625 3890 625 Q a L By 20 E q VPO2ETAYe KT TA DMO W p i oO 2000 Frequency Hz Figure 4 21 P AR Transmit Signal Frequency Spectrum Amplitude e Time mS Figure h 22 P AR Transmit Signal Envelope 4 30 HP h9h5A Measurement Principles RETURN LOSS Return loss is the ratio in decibels of the power incident upon a transmission system discontinuity to the power reflected from the discontinuity Return loss measurements are made on both 2 wire and 4 wire circuits The measurement indicates how well the input and the output impedances are matched throughout a circuit Four measurements are made when measuring return loss echo return loss ERL singing return loss low SRL low singing return loss high SRL high and sine wave return loss SWL ERL is the most critical of the four measurements SRL low and SRL high are designed to protect against circuit instability Figure 4 23 shows the filter shapes for the measurements Echo return loss ERL and singing return loss SRL are band average re
54. output key is pressed EXAMPLE PROGRAM WHEN USING THE HP 98164A HP 9826A or HP 9836A 10 Frequency run program 20 This program will do a frequency run between two user specified 30 frequencies with a user specified step and reference frequency i i 40 The program also inputs the transmit and receive impedances i 50 This program has a limit of 1000 points which is a function of 60 the array size 70 String into which data is read from the HP L945A rray in which relative level is stored Array in which frequency data is stored 80 DIM A 32 90 DIM Level 1000 100 DIM Freq 1000 110 120 OUTPUT 2 CHR 255 amp K 130 PRINTER IS 1 140 150 BEEP 160 INPUT AT WHAT ADDRESS IS THE 4945A Tims 1 170 IF Tims gt 700 AND Tims lt 731 THEN GOTO 200 i Is it gt 700 and lt 731 180 IF NOT lt Tims gt 0 and Tims 31 THEN GOTO 150 Did they enter 1 to 30 190 Tims Tims 700 i Using interface 7 add 700 l t i Clear screen Print on the screen Prompt for HP 4945A address ee ro Enter the HP h9h5A address 200 ASSIGN Tims TO Tims Tims is now the address of the HP 4Q45A 210 Set a 30 second timeout Clear the bus Clear the instrument Put it into REMOTE state Lock out the front panel 220 ON TIMEOUT 7 30 GOTO 1350 230 ABORT 7 240 CLEAR Tims 250 REMOTE Tims 260 LOCAL LOCKOUT 7 270 280 Prompt the user for transmit impedance en en famn 5 16 HP 4945A HP IB Operation Example P
55. poll configure disables the parallel poll response Disables the Parallel Poil response Returns service request status if enabled otherwise pas sive false is sent on data bus If it equals the modules address then it becomes listener active Unaddresses module if listener active If equal to modules address then it becomes talker active otherwise it is unaddressed if active talker The module is unaddressed if active talker Group Execute GET This command is ignored A byte that represents the operational conditions of a group of devices on the bus Each device responds on a particular bit of the byte thus identifying a device dependent condition This bit is sent by devices in response to a Parallel Poll operation The HP 4945A returns service request status on the specified bit if enabled aa 4 HP LOUSA HP IB Operation Table 5 2 HP IB Messages and HP 4945A Responses con t Message Definition and Response Pass Control Transfers the bus management responsibilities from the active controller to another controller Abort The system controller sends this message to uncondition ally take control of the bus from the active controller The message terminates all bus communications but does not implement the clear message When the Interface Clear line IFC is true the HP hOl5A does the following The interface is unaddressed Data in the queues is retained Co
56. priority priority priority priority HP 4945A I O Module Codes HP 49454 I O Module Codes TRANSIENTS In process TRANS TIMMN TIMSC NOTCH IMPLO IMPMD IMPHI PHHIT GNHIT DPOUT STLVL STFRQ WARNG ENDST Count period complete TRANS TIMMN TIMSC NOTCH IMPLO IMPMD IMPHI PHHIT GNHIT DPOUT STLVL STFRQ WARNG ENDST ER MIN T SEC DBRN FRFRUCHES 20 CNTS nere ONTIS RE CNTS TOR ONTE Wien CNTS Asc DBM aak a a daai Hz AA 0 0 MIN SEC DBRN FAT o ms aS CNTS iie eame eee CNTS ERAN ONTE Sek DEM kaai iei aa HZ XX 0 ENVELOPE DELAY No zero DLAY USEC AVGLV DBM FRQCY KAAKA EZ STLVL T1 DBM STFRQ HHH EH HZ WARNG XX ENDST O Transients running Elapsed time minutes Elapsed time seconds Noise with tone Impulse noise iow Impulse noise mid Impulse noise high Phase hits Gain hits Drop outs Status field level Status field frequency Warning message Highest priority End of set Transients stopped Elapsed time minutes Elapsed time seconds Noise with tone Impuise noise low Impulse noise mid Impulse noise high Phase hits Gain hits Drop outs Status field level Status field frequency Warning message Highest priority End of set Delay Average level Frequency Status field level Status field frequency Warning message Highest priority End of set 8 6 Level ze DLAY RLLVL LZRLV LZRFR FRQCY STLVL STFRQ WARNG ENDS
57. recommended that you use the test set at transmission levels gt 40 dBm and a S N ratio gt 20 dB since impair ments on the lines being used could disturb your Master Slave operation Always check your connections to ensure continuity Descriptions All error messages along with the equivalent H code used by the HP h943A and HP YOLLA are contained is this section These messages are generated by the master unit This section is organized to highlight some of the key differences between each of the error messages Below is a brief explanation of each of the areas When This refers to whether the error will occur while linking is in progress LINKING is flashing on the display or after link up Pilot Tone This will tell you whether you are receiving the pilot tone 1990 Hz Data Data refers to the FSK information which is being sent between the instru ments on the communications pair This will tell you if the error message is being caused because no data is being received by the Master from the Slave Direction of Test This is only applicable after link up Certain messages are suseptible to the direction of test which was selected This will list whether it will only happen when the instrument is making a measurement in a certain direction or if it occurs independent of the direction of test setting Problem Channel Occasionally you can isolate the problem to a specific channel The channel we refer to here is the p
58. return loss meaurement using one of the noise waveforms ERL SRL HIGH SRL LOW or using a single frequency tone To facilitate characterizing a line you can run a programmable frequency sweep over the band of interest in sine wave return loss Note This measurement is not available when operating in master slave mode To enter the return loss menu press the TEST SELECT hardkey and then the RETURN LOSS softkey 8 The following menu vill appear 10 55 AM Te 274 WIRE 1 RETURN LOSS 2 WIRE SINE URVE 0 0 dB SINE WAVE RETURN LOSS ERL 3 SRL LOU E SRL HIGH E MEASURE ALL 5 1 IRCY TERHI 1004 Hz 13 0 dBm PROGRAH i 1004 Hz 13 090 dBm SWEEP Figure 3 23 The Return Loss Measurement Menu 3 50 HP h9h5A Operation This softkey cycles through 2 WIRE AW O TLP LW 16 TLP It selects 2 or h wire and adjusts the levels amp ccording to the point in the circuit you are test ing at This softkey selects sine wave return loss This softkey selects echo return loss ERL This softkey selects singing return loss low SRL LOW This softkey selects singing return loss high SRL HIGH This softkey selects ERL SRL LOW and SRL HIGH simultaneously What is displayed on this softkey depends on whether you have selected 2 or 4 wire mode on softkey 1 If you are in 2 wire mode this key is labelled REFERENCE IMP It sets the reference impedance of the internal hybrid It cycles th
59. service was requested The lower six bits encode the various messages Bit five is low when an event has occurred and the status is reset when a serial poll is made When bit five is set the status reflects a state such as ready not ready The state is not affected by serial polling but will only be affected by the changing state of the instrument for ex ample when data is no longer available the data ready message is replaced by the all OK message The HP 18165A Interface responses to amp serial poll are listed below Decimal Binary Meaning 128 10000000 Nothing wrong no service requested 163 10100011 Master Slave initial link in progress or slave state 196 11000100 Device is in an invalid state 198 11000110 Self test failure 199 11000111 Command error 201 11001001 Front Panel service request 162 or 226 1x100010 Ready to send data The contents of the serial poll register are updated when the HP 4945A status is updated PARALLEL POLL OPERATION The HP 18165A Interface responde to a parallel poll if it is configured The in terface is configured for parallel poll from the controller Ihe parallel poll configure is done with the parallel poll enable command 100 1000SBBB ihe S bit indicates the sense of a devices response If S is a 1 the interface sets its bit if it needs service If S is a 0 the interface sets its bit if it does not need service The interface bit is identified by BBB 000 is bit O and 111 is bit
60. the HP 49454A HP 4945A Operation SEEAEVEN MEASURING SET Oc Figure 3 1 Front Panel Controls Connectors and Indicators HP 4945A Features FRONT PANEL DESCRIPTION 1 LINE ON OFF When pressed IN the instrument is powered ON When pressed again the power is turned on 2 SOFTKEYS The function of each softkey is labelled on the screen When a selection is made the next level of choices appears 3 SET UP Hardkey Pressing this key presents all of the set up choices All of the set up parameters can be changed from the menu selections available on the screen 4 TEST SELECT Hardkey Pressing this key presents all of the measurements selections 5 OUTPUT Hardkey Pressing this key will automatically print the data on the screen to a printer which is connected through any of the optional I O interfaces 6 NORMAL DISPLAY This returns the display to the normal display mode after being in special display mode 7 SPECIAL DISPLAY Pressing this key enables the bold mode This mode displays the measurement data in characters five times larger than normal display and in inverse video The special display mode can be used when the measurement data becomes difficult to read because of ambient light conditions or because of the distance from the display screen The SPECIAL DISPLY is designed to be used in the local mode When a controller is being used with the HP 4945A the measure ments should be viewed in NORM
61. the HP 4OLSA turned OFF insert the HP IL module HP 18165A into one of the ports on the rear panel 2 Connect the cables between the module and the printer 3 Press the LINE button IN to power ON the instrument 4 After the POWER ON SELF CHECK has PASSED then proceed to step 5 5 Press the SET UP hardkey 6 Next press the I O PORT SET UP softkey 4 If you plugged the module into PORT 2 then press PORT 2 SET UP softkey 8 The module should now be identified at the top of the screen 7 Press I O MODE softkey 1 until OUTPUT appears in parentheses 8 Configure your printer for LISTEN ALWAYS mode Note For the HP 82162A printer hold the PRINT button and the PAPER ADVANCE button down while powering on Your instrument is now ready to print any display by simply accessing the display perform the measurement and then pressing the OUTPUT hardkey HP h9h5A Operation Note Since the print buffer on the HP 821624 printer cannot hold all of the information on one line on the HP 4945A display some of the information will wrap around and be printed on the next line When using an HP IB printer If your printer is already connected to the HP IB module on your HP HOLSA then skip to step 3 da MV 8 With the HP 4945A turned OFF insert the HP IB module HP 18162A into one of the ports on the rear panel Connect the cables between the module and the printer Press the LINE button IN to power ON the ins
62. to the Description Section 3 23 HP h9h5A Operation Gain Slope Measurement If you press GAIN SLOPE softkey 1 in the Level Frequency menu the transmitter will automatically cycle through 404 Hz 1004 Hz and 2804 Hz 2 seconds step General Instructions Receiver is 2 Press the TEST SELECT hardkey Press the LEVEL FREQUENCY softkey 1 The Level Frequency menu will be displayed 1000 Hz Loss Measurement Instruct transmitter operator to send 1004 Hz tone Observe RCV LEVEL and RCV FREQUENCY in center of the display Press 60 Hz FILTER softkey until IN appears in parentheses If the received level changes more then 0 2 dBm the 60 Hz filter should be left IN throughout the measurement This will eliminate the effect of a 60 Hz signal interfering with your measurement Frequency Shift Measurement Observe the received frequency while communicating with the transmitter opera tor comparing any difference between the transmitted and received frequencies Note The transmitting test set must be a test set capable of transmitting a signal which is known within 0 5 Hz Attenuation Distortion Instruct the transmitter operator to send 1004 Hz tone If you want this mea surement to be made in absolute dBm then skip to step 9 Press the LEVEL ZERO softkey This establishes a 0 dB reference at the current frequency 1004 Hz Observe RCV LEVEL and RCV FREQUENCY in the center of the display while the agreed upon freq
63. to the following state Menu Test select Frequency 1004 Hz Display Level on HP h9hhA Envelope Delay mode TMT RCV Imp 600 ohms Rcv Term hold coils off SF skip off Voice limit off Master slave off Direction master to slave Talk bat off Self check full Mode T Segment x Stop on check end HP LOLSA I O Module Codes Mnemonic RESET con t Noise C msg filter 60 Hz filter Sweep Single From tep Rate Measurement Jitter Return loss Envelope delay Transients Level softkeys defaults Frequency softkey defaults Volume Level Monitor Beep TRMT RCV switch Hesets the queues stops any measurement in process normal direct mode is exited Function Data Entry noise with tone in out stopped 204 To 3904 100 fast level frequency Quiet term 1004 Hz 20 300 Hz band Amp and phase measure all 2 wire Hybrid loss 00 0 dB normal stopped 8 sec 15 mim 4 dB step 68 dB threshold 20 deg threshold 10 dB gain hit Imp 600 ohms 7 0 0 0 6 0 13 0 29 0 304 404 1004 2804 3004 2713 j off 3 receive on TRMT RCV Mode of instrument goes to Receive Transmit Transmit Receive hardkeys RXM XMR Recieve transmit no Transmit recieve no 8 22 Mnemonic SELF CHECK SCO SC1 SC23 SC3 mode SCh seg SC5 SC6 SCT SC8 SC9 Function Stop full diagnostics HP h9h5A I O Module Codes Data Entry Start full diagnostics Full self check
64. when in DATA ENTRY mode These will in crement or decrement the value of each press of the hardkey TRMI RCY Hardkeys or normal reverse keys The LED illuminated determines which terminals are connected to the transmitter and which are connected to the receiver To reverse the connections simply press the alternate hardkey HOLD Coil LEDs These LEDs are directly associated with the jacks located below them These indicate that the hold coils are active LED illuminated on the left and or right set of terminals Transmitter and Receiver Jacks Connections can be made using either the stan dard Western Electric 310 jacks or the binding posts The LEDs noted 13 in dicate which terminals are the transmitter and which are the receiver DIAL Posts These posts are provided for connection of a linesman s handset The dial post when activated are connected to the transmit terminals 3 3 HP LOLSA Operaticn a 3 n j SA MAAP US o7 2a LO HEO m e C fA CEED s MRD am i eae cen Hj eS GEI Y GS ene CARRS wom Tr GR emu Figure 3 2 Rear Panel Control Connectors and Features REAR PANEL DESCRIPTION 1 I O Module Panels These panels can be removed and the 1 0 modules can be in serted in their place 2 Jitter Output This is the demodulated jitter output By using this output you are able to directly observe what is causing the jitter impairment 60 Hz random noise etc This output is directly
65. 00 4800 9600 bps Asynchronous half or full duplex 7 or 8 bit word Parity none odd even mark or space R AH SH D T1 T5 Li AML CO DC2 DTC PP1 SR2 RL2 PDO DDO 135 600 900 or 1200 ohm Two circuits each independent gt 20 mA for applied open circuit voltages from 42 5 to 105 volts dc either polarity through an external resistance of 21700 ohms Nominal 23 mA 48 V 1300 ohms 20 dE from 28 Hz to 110 kHz gt 30 dB from 800 Hz to 110 kHz at 135 ohms gt 30 dB from 200 Hz to 20 kHz 1 4 HP h9h5A General Information Tabie 1 1 Specifications cont Bridging Loss receiver Longitudinal Balance receiver and transmitter Maximum dc blocking Transmitter Frequency Range Resolution Accuracy Sweep Step Size step Rate SF Skip Holding Tone Transmitter Level Range Resolution Accuracy ER lt 0 2 dB 90 dB 50 Hz to 120 Hz decreasing 6 dB per octave above 120 Hz 150 volts 20 Hz to 110 Hz selected by keypad or six programmable steps 1 Hz from 20 Hz to 9999 Hz 10 Hz from 10 kHz to 110 kHz 01 of output frequency Automatic single or repetitive or manual Automatic Programmable from 10 Hz to lOkHz Manual Selectable 10 50 100 1000 Hz 0 3 1 or 3 steps per second Skips a band from 2450 to 2750 Hz 1004 Hz 0 1 Hz 60 to 13 dBm 600 900 1200 ohm 60 to 5 dBm 135 ohm 0 1 dB 0 1 dB at 1004 Hz
66. 004 Hz when this menu is accessed No further adjustment is needed here Adjust the output level to the Data Level using the LEVEL hardkey Note All transmission measurements should be made at Data Level The Data Level for data circuits is a power of 13 dB below the Transmission Level Point TLP For exam ple if the TLP is 16 dB the Data Level would be 29 dBm Therefore an output level of 29 dBm would be ap plied in this case 3 46 HP 4945A Operation General Instructions Receiver 1 Press the TEST SELECT hardkey 2 Press the JITTER softkey 6 The Jitter menu will be displayed 3 To perform the amplitude jitter measurement press softkey 1 until ON appears in parentheses 4 To perform the phase jitter measurement press softkey 2 until ON appears in parentheses 5S To perform the selected measurement in all three bandwidths press the MEASURE ALL softkey 6 and skip to step 7 6 Select the desired measurement bandwidth by pressing the appropriate softkey 3 20 300Hz 4 4 300Hz or 5 4 20Hz T Observe the jitter readings on the display If the readings vary take the average 3 47 HP 4945A Operation P AR PEAK TO AVERAGE RATIO MEASUREMENT Description P AR should not be used as a conclusive troubleshooting tool but only as a quick check of a line s performance The P AR signal is sensitive to attenuation distor tion phase distortion and noise To enter the P AR menu press
67. 1983 First Edition May 1985 Second Edition ii TABLE OF CONTENTS Chapter i GENERAL INFORMATION introduction lt are FO WS EN ERROR BPECILICHT I ONE ee en ee p ee Safety ConstderstJons susanne u Instruments Covered by This Manual TREE RR Descriptio area EEE Vg edite oe ais HP IB Hewlett packard Interface Bus UOTE HP IL Hewlett Packard Interface Loop RS 232C iude aues das PPS E ce er pet A dae ccessories TEN EEE E PES ODtlohs coe 4 dos anb v ios V o s P da ot voa ch eR d RN i INSTALLATION Introd stiondoio cuu pA SL Qd au D ERAS Tm Initial Inspection seime oee a ee en m Preparation for Tse nassen Power Requirements Ore EVE A c apa ETATE e Line Voltage Selects ones os et breeds ae nase Power Cable Van a gods ignite eee ee i Sede Storage and Shipment oe ee ee UIT Environment TRIERER Terr ee ree Original PacRap ThE yi vea Ac e na wee e ME hd Other Packaging box l de dora iacu 8 SUR A Ca e ra ne HI OPERATION HP 4945A Features ea Front Panel Description isa ek en Rear Panel Deseriptl l 4 659959 DR US oe end ene CRE Display Functions es nerpa A OPE GEN SEX bs Operating the HP h9hH5A REITER ES Ss Data Entry Procedure POLS REE 93 a a P aptius Power on Self Check salat Set Up and Turn On ProsceQUuYe iie vk eee Level and Frequency cressa pa E E NARI ETE S ated NOlSe
68. 407 Receiver ROM 3 A000 BFFF bad checksum 014 A10 U308 Receiver ROM 4 8000 9FFF bad checksum 015 A10 U307 Receiver ROM 5 6000 7FFF bad checksum 016 A10 U306 Receiver ROM 6 4000 5FFF bad checksum O17 A10 U305 Receiver ROM 7 2000 3FFF bad checksum 018 A9 Uh00 Transients Board ROM checksum error 100 Ali U60h System start up ROM bad loc cade 101 A12 U100 Main ROM 1 6000 9FFF bad loc code 102 A12 U200 Main ROM 2 A000 DFFF bad loc code 103 Al2 U300 Bank 1 ROM 2000 5FFF bad loc code 104 A12 UhO0 Bank 2 ROM 2000 5FFF bad loc code 105 Al2 U102 Bank 3 ROM 2000 5FFF bad loc code 106 12 U202 Bank ROM 2000 5FFF bad loc code 107 A12 U302 Bank 5 ROM 2000 5FFF bad loc code 108 12 U10h Bank 6 ROM 2000 5FFF bad loc code 109 A12 U204 Bank 7 ROM 2000 5FFF bad loc code 111 A10 U607 Receiver ROM 1 EO00 FFF bad loc code 112 A10 U507 Receiver ROM 2 C000 DFFF bad loc code 113 A10 UhO7 Receiver ROM 3 A000 BFFF bad loc code 114 A10 U308 Receiver ROM 4 8000 9FFF bad loc code 115 A10 U307 Receiver ROM 5 6000 7FFF bad loc code 116 A10 U306 Receiver ROM 6 h000 5FFF bad loc code 117 A10 U305 Receiver ROM 7 2000 3FFF bad loc code 118 A9 Uh0O0 Transients Board ROM bad loc code 200 A11 U60h System start up ROM bad rev code 201 A12 U100 Main ROM 1 6000 9FFF bad rev code 202 Al2 U200 Main ROM 2 A000 DFFF bad rev
69. 7 The inter face must be listen addressed to be able to respond to this command HP h9hN5A HP IL Operation Either the parallel poll disable or the parallel poll unconfigure can be used to disable parallel polls The listen address devices respond to the PPD while all devices repond to the PPU command USING THE HP 41C AS A CONTROLLER An HP 41C with the HP 82160A HP IL module can be used to control the HP hOh5A The HP 82183A Extended I O module is useful to allow more general loop operation when there are several devices in the loop SAMPLE PROGRAM USING THE HP 4iC VOICEBAND FREQUENCY RUN The following is a sample HP 41C program designed to do a frequency run over the voiceband from 304 Hz to 3904 Hz in 100 Hz steps and print the results on an HP 82162A thermal printer which is also on the HP IL loop For this program to work properly the HP 4O4S5A should be the first device on the loop and the HP 82162A should be the second Comments to the program listing have been added following the for clarity A bar code program for use with an HP 82153A Wand and HP ic is also shown set Up Section 01 LBL FRQRUN Program name l 02 CF 29 Delete commas from numeric data 999 03 FIX 1 Only need 0 1 resolution 04 STOP10 Reset the loop 05 47 The HP h9h5A is the first device on the 06 SELECT loop gt address one 07 REMOTE Put the HP 4OQ4U5A in remote state 08 ADV Linefeed the 8216 A thermal printer 09 RST TR2 TR6
70. 7 3 NO a a ee E Er E tal 7 3 UN an she hace M eius aae dae ve RAE P IM RE Fes apes d etal 7 4 z HP h9h5A Table of Contents Chapter VH RS 232 OPERATION con t Half Duplex is seeds ux No Handshake Full Handshake Software Handshake ECNO a doe pv e rx eae TT PEN Local Lockout Status Reporting Controlling the HP 945A Vill I O MODULE CODES Introdgucti n l 153 4 45 e e owe 9 9 4 9 4 5 e ee 9 n oe 09 E ox a ter sees 4 oo t t amp 9 0 9 o9 o r 9 o5 t r ee ee ee a ewe terzas t Tr 9 9 9 9 5 5 3 8 4 9o to o9 9 d 9 9 9 3 9 9 eee 9 9 9 29 9 4 9 49422 5 tswa LIE 4 s Se 9 9 9 t 3 8 E 4 2 9 a 9 9 O amp 9 4 9 o 9 9 9 4 4 4 9 c9 9 o 4 9 v9 ee 4 9 9 wee oe ee 4 o 9 amp 9 s 9 I e st 8 ot 9 Output Format to the Controlling Interface Output Sequences I O Mnemonic Commands APPENDIX A Introductionoiur x za 5 Power on Self Check Error Codes Mainframe Error Codes Interface Error Codes DXIaEnOStlO6Bi es d wp oe f o4 9 9 9 9 9 9 cs 9 c f traer 7 4 9 9 we oe 9 5 5 ae ae 9 99 979 9 s re eee oer ee ae ae e t 5259 eee t tree 5 ae ear 9 ewe 9 2 9 5 9 e 4 34975 5 en 9 9 3 vi se 29 2 9 7 o 8 9 5 amp 9 4 c e o o Page NN NNN M
71. 9 10 0 10 776 Hz 0 dBm 600 10 i 0 20 840 Hz O dBm 600 11 12 thru 16 not used HP OSA Operating Verification Diagnostics Mode 21 MODE 21 Transient Measurements Check A1 A2 A4 A8 A9 A17 A 1004 Hz 775 Vrms sine wave from A17 is sent to the Al input multiplexer Impulse noise is monitored through the wideband autorange with the C message filter and the 1010 Hz notch filter switched in and measured on A8 Gain hits phase hits and dropouts are monitored through the narrowband autorange with the bessel filter switched in Phase impairments are generated by programming frequency transitions into the transmitter and checked with the 20 degree phase hit detector The gain hits detector is checked at the 2 dB and 6 dB threshold settings and checked against the receiver fine attenuator The 12 dB dropout detector is also checked against the fine attenuator The transmitter is then set to 1800 Hz to bypass the notch filter and the impulse noise thresholds are checked at 2 dB and 6 dB levels In this case the transmitter fine attenuator provides the reference The fast count rate is checked by allowing a five second impulse noise count at 100 counts per second on a signal which should count all the time Following is a summary of the Mode 21 tests Results Data Displayed Segment Test Shouid Be Path L PLL Balance Constant e 20 Degree P H Constant i 3 20 Degree P H Constant 4 2 dB Gain Hit Constant 2 5 2 dB Gain
72. A Operating Verification Diagnostics Mode 46 PERFORMANCE VERIFICATION AND SERVICE AID MODES Several modes of operation are available within the HP 4945A receiver to assist in evaluating the HP 4945A performance and troubleshooting the receiver measurements As with the diagnostic self checks these modes are accessed through the self test menu These modes allow high resolution measurements through the receiver independent of the HP 4QU5A measurement restrictions These modes allow static setup conditions for troubleshooting Mode 46 Filter Response Checks This performance verification mode uses the receiver as a voltmeter and uses a different filter for each path An external signal is input to the receiver Depending on the path selected one of the HP 4G45A filters is switched into the Signal path By varying the signal frequency the response of the filter can be checked by comparing the dB readings displayed with the values given in the response charts The true voltage and power of the signal are given These measurements assume ideal termination impedances within the receiver To use this mode refer to the individual filter tests in Section IV of the HP HOSA Service Manual Performance Tests 4 9 through 4 15 HP 49454 Operating Verification Diagnostics Modes 47 and 48 Mode 47 DC Offset Settling Time narrowband This mode checks the de offset settling times in the narrowband autorange amplifier when the gain is
73. AL DISPLY de ils 12 13 14 15 vreration DATA ENTRY Keys These keys are used to enter numeric values when prompted by the DATA ENTRY block on the display After the desired value has teen keyed in the ENTER key must then be pressed to end the data entry mode VOLUME Hardkey The volume level can be adjusted by the data entry keys or the up down arrow keys Also the keyboard beep can be turned ON or CFF LEVEL Hardkey Pressing this key enables you to change the existing output level by a number of methods Along the right side of the screen 5 program mable levels and a quiet termination selection are labelled By pressing any of these the level automatically changes to the desired value in addition the data entry block which is in inverse video indicates that the data entry keys are active The up down arrow keys allow you to step to the desired level The step size used is set on softkey 7 on this menu FREQUENCY Hardkey Prassing this key allows you to change the transmit frequency by a number of methods Along the righ side of the screen 6 prc grammable frequencies are labelled Pressing any of these changes the frequency to the desired value In addition the data entry block which is in inverse video indicates that the data entry keys are active The up down arrow keys allow you to step to the desired level The step size used is set on softkey 7 on this menu UP DOWN Arrow Keys These are active
74. AND Ref _fre lt 110004 THEN GOTO 190 Prompt the user for start frequency BEEP INPUT WHAT IS THE STARTING FREQUENCY Start fre Do a range test on the start frequency i IF NOT Start fre 20 AND Start fre 11000h THEN GOTO 590 IF NOT Tr imp 135 THEN GOTO 690 IF NOT Start_ fre gt 200 AND Start fre lt 110004 THEN GOTO 590 I Prompt the user for stop frequency BEEP HP h9h5A HP IB Operation Example Program con t 700 710 720 730 740 150 760 TTO 780 790 800 810 820 830 BuO 850 860 870 880 890 900 910 920 930 940 950 960 970 980 990 1000 1010 1020 1030 1040 1050 1060 1070 1080 1090 1100 1110 1120 1130 1140 1150 1160 1170 1180 1190 INPUT WHAT IS THE STOPPING FREQUENCY Stop fre gt i Do a range test on the stop frequency t IF NOT Stop fre 20 AND Stop fre lt 110004 THEN GOTO 690 IF NOT Tr imp 135 THEN GOTO 810 IF NOT Stop fre 200 AND Stop fre 11000h THEN GOTO 690 i Then do a test to assure that the stop frequency is larger than the start frequency If start gt stop re enter IF NOT Start fre Stop fre THEN GOTO 590 i i l Prompt the user for the step size BEEP INPUT WHAT IS THE STEP FREQUENCY Step fre i Calculate the number of points in the run must be 1 to 1000 Size INT Stop fre Start fre Step fre IF Size 0 THEN GOTO 80 i IF NOT Size 1000 THEN GOTO 9h0 DISP SORRY ONLY 1000 POI
75. ATION DISTORTION MEASUREMENT Description The HP 955A performs the intermodulation distortion measurement using the li tone technique This measurement determines the effect of line nonlinearities on the transmitted signal The HP 49O45A will transmit a multifrequency signal and measure the second and third order distortion products The HP 4Q45A has the capability to run a signal to noise check and correct the readings based on the results This op tion is enabled when you select CHECK SIGNAL in the IMD menu To enter the intermodulation distortion menu press the TEST SELECT hardkey and then the IMD NLD softkey 5 The following menu will appear 09 28 83 10 53 AH CHECK INTERMODULATION DISTORTION SIGHAL SIGNAL LEVEL 13 0 dBm SIGNAL 2ND ORDER 79 dB SIGNAL 3RD ORDER t dB RCY TERMI ONES 13 0 d Figure 3 20 The Intermodulation Distortion Measurement Menu 1 This softkey enables a 12 second check signal with each press which is used to determine the signal to noise correction factor Ul Licensed under Hekimian Laboratories Inc U Patent No 3 862 380 for nonlinear distortion analyzer 3 42 HP h9h5A Operation Not Used Not Used Not Used Not Used Not Used Not Used Not Used General Instructions Transmitter ls s 3 Press the TEST SELECT hardkey Press the IMD NLD softkey 5 The IMD menu will be displayed Adjust the output level to the Data Level using the LE
76. BM STFRQ HHH HH HZ WARNG XX ENDST 0 Amplitude jitter 20 300 Hz If amp jitter is on Phase jitter 20 300 Hz If phase jitter is on Status field level Status field frequency Warning message Highest priority End of set 8 8 JITTER con t 20 300 Hz Amplitude AMPJH PK STLVL DBM STFRQ ee ue WARNG XX ENDST 0 20 300 Hz Phase PHJHI DEG STLVL DBM STFRQ HZ WARNG XX ENDST 0 HP 4OhSA I O Module Coddes Amplitude jitter 20 300 Hz If amp jitter is on Status field level Status field frequency Warning message Highest priority End of set Phase jitter 20 300 Hz If phase jitter is on Status field level Status field frequency Warning message Highest priority End of set 20 300 Hz neither amplitude or phase STLVL DBM STFRQ x xXx HZ WARNG XX ENDST O Status field level Status field frequency Warning message Highest priority End of set 4 300 Hz Amplitude and phase JFUL Fy PK PJFUL DEG STLVL DBM STFRQ LEX EE E HZ WARNG XX ENDST O 4 300 Hz Amplitude AJFUL PK STLVL DBM STFRQ He He HH EZ WARNG XX ENDST 0 4 300 Hz Phase PJFUL DEG STLVL DBM STFRQ je REX X HZ WARNG XX ENDST O Amplitude jitter 4 300 Hz If amp jitter is on Phase jitter h 300 Hz If phase jitter is on Status field level Status field frequency Warning message Highest priority End of set Amplitude jitter h 300 Hz
77. C For the self test results the following format is used lt LN gt lt line no in ASCII gt lt space gt lt data gt lt suffix gt lt CR gt lt LF gt The header consists of LN the line number and a space It is always six charac ters long which is the same as the normal data type headers Data types 96 through 185 all have the header SCMOD PUT PNO LN 1 LN 16 64 79 DT1D DT16D LN 1 LN 16 80 95 DTOl DT9O SCMOD 96 185 8 3 HP hOh5A I O Module Codes The following warning messages will appear on the display in the warning field when the limits of a paramater are exceeded HEADING MESSAGE WARNG O BLANK WARNING FIELD WARNG 1 NO HOLDING TONE WARNG 2 NOISE WITHIN 12 dB LO THRESH WARNG 3 IMD SIGNAL NOT RECEIVED WARNG 4 2nd ORDER DIST NOISE lt 2dB WARNG 5 3rd ORDER DIST NOISE 2dB WARNG 6 2nd 3rd ORDER DIST NOISE 2dB WARNG 8 NO ANSWER RECEVED FROM SLAVE WARNG 9 DATA ERRORS IN SLAVE RESPONSE WARNG 10 BAD DATA IN SLAVE RESPONSE WARNG 11 INCORRECT RESPONSE FROM SLAVE WARNG 12 SLAVE FAILS TO EXECUTE COMMAND WARNG 13 SLAVE LOOPED BACK WARNG 15 NO DATA RECIEVED FROM SLAVE WARNG 16 RECIEVED LEVEL OUT OF RANGE WARNG 17 NO CARRIER RECEIVED FROM SLAVE WARNG 19 SLAVE INITIATED A MASTER SLAVE LINK ABORT WARNG 20 DROPOUT OF gt 1 SECOND TEST ABORTED WARNG 22 INVALID TEST SIGNAL WARNG 23 UNABLE TO COMPLETE MASTER SLAVE LINK WARNG 24 SLAVE UNABLE TO DO MEASUREMEN
78. DST Examples are TIM all OI HP IB and OE RS 232 Note that these commands will cause data to be sent to the controller but the data will not be terminated by the ENDST string this being reserved for data measured by the receiver CHANGE FREQUENCY COMMAND FRO lt freq gt Change transmitter frequency yes ERIS Frequency 1 no FR2 Frequency 2 no FR3 Frequency 3 no FRH Frequency 4 no ERS Frequency 5 no FR6 Frequency 6 no FR7 Step size 10 Hz no FR Step size 50 Hz no FRO Step size 100 Hz no FRA Step size 1000 Hz no FRB lt freg gt Program frequency 1 yes FRC lt freg gt Program frequency 2 yes FRD lt freg gt Program frequency 3 yes FRE freq Program frequency 4 yes FRE lt freg gt Program frequency 5 yes FRG lt freq gt Program frequency 6 yes INTERMODULATION DISTORTION IMO Normal test no IM Check signal no 8 16 Mnemonic Function IMPULSE NOISE TRANSIENTS INO IN1 IN2 IN3 IN INS IN6 ENTE INS ING INA INB INC IND INE INF ING INH INI INJ INK INL INM INN INO INP INQ INR INS cnt time INT lt thrshld gt I O SET UP COMMANDS 100 101 IO2 103 Ioy 205 IO 6 107 lt address gt Stop Start Count rate 7 second Count rate 8 second Count rate 100 second Data Entry Impulse threshold spread 2 dB Impulse threshold spread 3 dB Impulse threshold spread 4 dB Impulse threshold spread 5 dB Im
79. E 0 5 LIO BRBUND C HESSRGE FILTER IN i E ERNI y dBm P4 ER 8 Figure 3 14 The Noise Measurement Menu 3 26 HP h9h5A Operation Not Used This softkey selects the noise with tone measurement It measures the tele phone cicuit noise in dBrn in the presence of a 1004 Hz tone When this softkey is pressed the signal to noise ratio of the circuit is calculated This softkey selects the message circuit noise measurement It measures the telephone circuit noise with the line quiet terminated This softkey selects the noise to ground measurement This can be used as an indication of line balance Not Used Not Used This softkey accesses the noise filters menu If you press softkey 8 SELECT FILTER you will access the following menu 09 28 83 10 49 AM NOISE FILTERS aaa NOISE WITH TONE 28 dBrn 3kHz FLAT C HESSRGE 1SkHz FLAT PROGRAH 50 kBIT C MESSAGE FILTER IN I IRCV TERHI 1004 Hz 7 0 dB 1004 Hz rau Figure 3 15 The Noise Filters Menu Seel HP 4O4SA Operation l This softkey selects the C message filter This filter weights the noise to similulate what the human ear would detect 2 This softkey selects the 3 kHz flat filter This filter is used to detect the presence of low frequency noise on voice circuits 3 This softkey selects the 15 kHz flat filter This filter is used when making unweighted measurements of noise on program circuits h This softkey selects
80. E When making a data entry the HP h9h5A automati cally displays the allowable range for that parameter If you try to exceed this range the XX OUT OF RANGE indication appears with a warning beep TURN DIAL TALK OFF TO EXIT If you are in DIAL HOLD SET UP menu you are not al lowed to exit unless you turn DIAL TALK OFF This is to prevent you from making a measurement without the instrument connected to the line NO I O MODULE IN OUTPUT MODE This indicates that the OUTPUT hardkey was pressed but an I O module is not installed or was not set up in output mode PRINTING This occurs when data is being sent out to a printer The HP 4G45A is equipped with self diagnostics and self calibration capability When running either of these routines one of the following messages will be displayed CALIBRATING This message is displayed when running the calibration routine SINGLE or REPEATING CHECK IN PROGRESS This message is displayed when running the diagnostic self check LINKING PLEASE WAIT This message indicates that it is performing the initial master slave linkup AREA 5 MESSAGES SELF CHECKS PASSED SELF CHECKS FAILED These messages are displayed in the diag nostic self check mode They are followed by the number of times it has passed and or failed RCV TERM or RCV BRDG This indicates whether your receiver is bridged or terminated SF SKP This indicates that the SF signalling frequency SKIP is active VOICE Thi
81. E 3 Basic Transmitter Check A5 A15 This mode connects the self test signal ST16 from A15 directly to the A5 input multiplexer A 1024 Hz 775 Vrms sine wave is transmitted and measured with the FWA wideband and RMS detectors Paths 1 and 2 The same signal is then transmitted with an additional 10 dB of loss introduced by the fine attenuator on A15 and again measured by the two detectors Paths 3 and 4 In the last segment Path 5 the signal is set to 775 Vrms and a rough frequency check is made by setting the A5 comparator threshold to 33 V and measuring the time between threshold crossings by the FW rectified signal Following is a summary of the Mode 3 tests Results Displayed Shouid Be Data Segment 1 FWA voltage in mV 698 20 1 2 RMS voltage in mV 113 20 2 3 not used 4 FWA voltage 10 dB 221 20 3 5 RMS voltage 10 dB 245 20 4 6 not used 7 Time in microseconds 1024 30 5 8 thru 16 not used A 10 HP h9li5A Operating Verification Diagnostics Mode 4 MODE 4 Wideband Autorange Amplifier Check A4 A15 A17 This mode checks the transmitter course attenuator on Al7 the transmitter fine attenuator on A15 and the wideband autorange amplifier on Ah The displayed numbers represent the rms voltage output of the wideband autorange channel under all gain conditions The rms voltage can be verified with an external rms voltmeter at Ah TP5 A single failur
82. EASUREMENT Transmitter Level Range 40 to O dBm Modulation Frequency 83 1 3 Hz 0 1 Receiver Level Range 40 to 10 dBm Measurement Range 3000 to 9000 microseconds Besen 1 microsecond Accuracy 10 usec from 600 to 4000 Hz 30 usec from 300 to 600 Hz RETURN LOSS MEASUREMENT Modes j ERL SRL High SRL Low and Sine Wave Two Wire Return Loss Level Range 10 to 2 dBm Measurement Range O dB to 4O dB Resolution 0 1 daB Reference Impedance 600 or 900 ohms 1 in series with 2 16 microfarads 1 or External Four Wire Return Loss Transmitter Level Range 10 to 2 dBm Receiver Range O dB to 50 dB Accuracy 0 5 dB Resolution 0 1 dB Transhybrid Loss Compensation 10 to 30 dB HP 4945A installation CHAPTER Il INSTALLATION INTRODUCTION This section contains installation instructions for the HP 4945A This section also includes information about initial inspection and damage claims preparation for use packaging for shipment and storage requirements WARNING To avoid hazardous electrical shock do not perform electrical tests when there are signs of shipping damage to any portion of the outer enclosure covers panels CRT etc INITIAL INSPECTION Inspect the shipping container for damage If the shipping container or cushioning material is damaged it should be kept until the contents of the shipment have been checked for completeness and the instrument has been checked m
83. ET TERMINATION LINE MONITOR PROGRAM S K BIT Figure 4 3 Message Circuit Noise Measurement The 3 kHz flat filter has a response that provides much less attenuation to the low frequencies 60 Hz to 500 Hz than the C message filter By comparing a 3 kHz fiat noise measurement to a C message noise measurement the relative influence of low frequency noise 60 Hz commercial power 20 Hz ring etc can be determined The program filter is used for weighted measurements of noise on program circuits that have bandwidths up to approximately 8 kHz It is not used on voice message circuits The 15 kHz flat filter is used when making unweighted measurements of noise on pro gram circuits It is a 15 kHz low pass filter and it is not ordinarily used on voice message circuits The 50 Kbit filter is used to measure noise on facilities using up to 56 Kbit data service The filters are used on wideband data circuits at an impedance of 135 ohms Received noise levels are displayed in units of dBrn dB with respect to noise where 0 dBrn 90 dBm For example a noise reading of 20 dBrn has an RMS power of 70 dBrn 20 90 70 With the C message filter selected displayed readings are interpreted as being in units of dBrnC noise level in dBrn with a C message weighted measuring device Single frequency interference refers to unwanted steady tones which may appear on voice channels Occassional burst of low level tones which may occur from
84. H2 PLL not used not used not used 20Hz PLL LHe PLL not used 20Hz PLL hHz PLL Lock Lock Lock Lock Lock Lock Results Displayed should Be 2 128 10 128 10 255 0 10 0 50 0 0 50 0 0 50 0 0 50 0 0 50 0 0 50 0 A 2h Path HP h9l5A Operating Verification Diagnostics Mode 18 MODE 18 Jitter Calibration A6 This mode calibrates the jitter circuits with signals from the transmitter and then checks the resulting calibration constants to within reasonable limits This test is a functional test as opposed to a performance test Following is a summary of the Mode 18 tests Results Data Displayed Segment Test Should Be Path 1 AJ OFFSET 4 300HZ 0 10 0 1 2 PJ OFFSET h 300HZ O 10 0 e 3 AJ OFFSET 20 300HZ 0 10 0 3 4 PJ OFFSET 20 300HZ O 10 0 4 5 AJ OFFSET 4 20HZ O 10 0 5 6 PJ OFFSET 4 20HZ 0 10 0 T AJ GAIN 4 300HZ 1485 100 7 8 PJ GAIN 4 300R2 688 125 8 9 AJ GAIN 20 300HZ 1485 100 9 10 PJ GAIN 20 300HZ 688 125 16 11 AJ GAIN 4 20HZ 1485 100 il 12 PJ GAIN l4 208Z 688 125 12 13 thru 16 not used HP 4O45A Operating Verification Diagnostics Mode 19 MODE 19 Envelope Delay Hardware Check A4 A5 A7 A14 A17 This mode verifies the AT hardware and its accuracy A transmit signal from A1T is sent to the Al input multiplexer The signal is sent through the Ah wideband amplifier to Af where it goes through the HI Q filter and then to the A45 F
85. HH HK HZ XX 0 Status field level Status field frequency Warning message Highest priority End of set all Amplitude and phase PK ok DEG He o PK DEG PK DEG DBM HHH HH HZ XX 0 we O eH 0 HN KEK Amplitude jitter 20 300 Hz If amp jitter is on Phase jitter 20 300 Hz If phase jitter is on Amplitude jitter 4 300 Hz If amp jitter is on Phase jitter 4 300 Hz If phase jitter is on Amplitude jitter 4 20 Hz If amp jitter is On Phase jitter 4 20 Hz If phase jitter is on Status field level Status field frequency Warning message Highest priority End of set 8 10 JITTER con t Measure all Amplitude AMPJH AJFUL AMPJL STLVL STFRQ WARNG ENDST Measure PHJHI PJFUL PHJLO STLVL STFRG WARNG ENDST Measure STLVL STFRQ WARNG ENDST PAR PAR P AR UNITS HEH PK PK PK DBM XexxX HZ XA 0 all HH HH KE tH Phase DEG DEG DEG DBM HH SEH HH HZ AA 0 HP h9h5A I O Module Codes Amplitude jitter 20 300 Hz If amp jitter is on Amplitude jitter 4 300 Hz If amp jitte Amplitude jitter 4 20 Hz If amp jitter Status field level Status field frequency Warning message Highest priority End of set Phase jitter 20 300 Hz If phase jitter is on Phase jitter 4 300 Hz If phase jitter is on Phase jitter 4 20 Hz If phase jitter is on Status field level Status field frequency Warni
86. Hit Constant 2 6 6 dB Gain Hit Constant 3 T 6 dB Gain Hit Constant 3 8 12 dB Dropout Constant 4 9 95 dBrn I N HI Constant 5 10 93 dBrn I N MID Constant 5 11 01 dBrn I N LOW Coustant 5 12 101 dBrn I N HI Constant 10 T 6 13 95 dBrn I N MID Constant 64 6 6 14 89 dBrn I N LOW Constant Qi U 6 15 100 Counts sec Constant 500 20 T 16 not used A 29 HP 4945A Operating Verification Diagnostics Mode 22 Mode 22 A3 FSK Demodulation Check A1 A2 A3 A14 A17 The transmitter signal on A17 is connected to A18 using the 2W XMT line From A18 the RTL T and RTL R signal is hardwired to A1 On A1 the signal goes through the differential input and then goes to A3 on the FSK SIGNL line The FSK signal at 75 Vrms is sent through the FSK demodulator on A3 Data is sent by the transmitter through the ACIA chip on All The data is decoded and compared to ensure a match If the demodulation circuit is not working an error shows as an unmatched data pair or an error flag indicating bad parity overrun or framing Following is a summary of the Mode 22 tests Results Data Displayed Segment Test Should Be 1 01 ACIA Data 1 2 02 ACIA Data 2 3 0h ACIA Data 4 4 08 ACIA Data 8 5 10 ACIA Data 16 6 20 ACIA Data 32 7 lO ACIA Data 6l 8 80 ACIA Data 128 9 FE ACIA Data 254 10 FD ACIA Data 253 11 FB ACIA Data 251 12 F7 ACIA Data 247 13 EF ACIA Data 239 14 DF ACIA Data 223 15 BF ACIA Data 191 16 7F ACIA Data 127 A 30 HP hOl5
87. If amp jitter is on Status field level Status field frequency Warning message Highest priority End of set Phase jitter h 300 Hz If phase jitter is on Status field level Status field frequency Warning message Highest priority End of set 8 9 HP h9h5A I O Module JITTER co L 300 Ez STLVL STFRQ WARNG ENDST 4 20 Hz AMPJL PHJLO SILVL STFRQ WARNG ENDST 4 20 Hz AMPJL STLVL SIFRQ WARNG ENDST 4 20 Hz PHILO STLVL STFRQ WARNG ENDST 4 20 Hz STLVL STFRQ WARNG ENDST Measure AMPJH PHJEI AJFUL PJFUL AMPJL PHJLO STLVL STFRQ WARNG ENDST Codes n t neither amplitude or phase x o3 DBM KHREEKM HZ XX 0 Amplitude and He X PK UC T DEG HHH o DBM HH HHH HZ XX 0 Amplitude HH R PK PR RU DBM x Xxx HZ EX 0 Phase 72 DEB x ok DBM MH HEH EZ XX 0 Status fieid level Status field frequency Warning message Highest priority End of set phase Amplitude jitter 4 20 Hz If amp jitter is on Phase jitter 4 20 Hz If phase jitter is status field level Status field frequency Warning message Highest priority End of set Amplitude jitter 4 20 Hz If amp jitter is on Status field level Status field frequency Warning message Highest priority End of set Phase jitter 4 20 Hz If phase jitter is on Status field level Status field frequency Warning message Highest priority End of set neither amplitude or phase BER Gk DBM H
88. K from the receiver the transmitter sends its block of information This process is repeated for each block A block can be up to 96 characters so there must be enough room in the receive buffer before the ACK is sent This protocol is used with either full or half duplex is sent This protocol is used with either full or half duplex 172 HP 4OL5A RS 232C Operation The Xon Xoff handshake is called receiver protocol because the receiver controls the handshake The interface monitors its buffer When there are 32 characters in the buffer the interface sends an Xoff to the transmitter to stop the data flow This allows room for one more block of 96 characters from the transmitter When the buffer empties to ten characters or less the interface sends an Xon to start the transmitter data flow The interface must be full duplex to use Xon Xoff protocol The external device controls the data flow when the interface is transmitting The 18163A will transmit at most two characters after it receives a XOFF Echo The interface is put into echo mode when the external device sends the mnemonic ONE command In full duplex operation characters are echoed as they are received In half duplex operation the interface waits for an ENQ if it is using the ENQ ACK handshake or a line feed if not in ENQ ACK before turning the line around and echoing the entire string In half duplex operation all command strings should be followed by CrLF Echo mode c
89. NSTOP allows you to con tinuously sweep 3 Enter the frequency you want the sweep to start from 4 Enter the frequency you want the sweep to end on 5 Enter the step size you want between the frequencies 6 Select how fast you want the sweep to step The key cycles through slow 3 steps second medium 1 step second and fast 3 steps second 7 Not Used 8 HP h9h5A Operation This softkey will return you to the envelope delay menu Note Due to the amount of time the receiver of the HP l9l5A needs to correctly measure a level and frequency some points will not be displayed when using the medium or fast sweep rates Master Slave Operation When using the instrument in master slave mode the STEP RATE softkey 6 will be blank The step rate is not selectable in this mode of operation General instructions Return Reference Normal Test Set t 2 Press the TEST SELECT hardkey Press the ENVELOPE DELAY softkey 4 The Envelope Delay menu will be displayed Press the NORMAL REPT softkey 1 until NORMAL appears in parentheses Connect the pair to be tested to the TRMT terminals Connect the return reference pair to the RCV terminals Adjust the output level to the Data Level using the LEVEL hardkey Note All transmission measurements should be made at Data Level The Data Level for data circuits is a power of 13 dB below the Transmission Level Point TLP For example if the TLP is 16
90. NTS ALLOWED GOTO 840 Go to level frequency at reference settle and zero the level OUTPUT Tims LFO FRO Ref fre WAIT 5 OUTPUT GTims ZLV EXC This is the measurement loop itsel FOR I 0 TO Size FrequencysStart fre I Step fre OUTPUT GTims FRO Frequency EXC Compute frequency Change frequency ask for amp set of data Get a piece of data Is it relative level Then store it in the array GOSUB Get string IF A 1 5 lt gt RLLVL THEN GOTO 1050 Level I VAL A 6 Get a piece of data Is it frequency Then store it in the array GOSUB Get string IF A 1 5 FRQCY THEN GOTO 1080 Freq I sVAL A 6 Get a piece of data Is it end of set GOSUB Get string IF A 1 5 lt gt ENDST THEN GOTO 1120 NEXT I Make the next measurement LOCAL T7 Return HP h9h5A to LOCAL state GOTO 1370 End eme em oem otee eee sme u gc nn Ph ec sen am ome s s o 5 18 Example Program con t 1200 1210 1220 1230 1240 1250 1260 1270 1280 1290 1300 1310 1320 1330 1340 1350 1360 1370 Get string S SPOLL Tims IF NOT BIT S 4 THEN GOTO 1270 ENTER Tims A RETURN IF S 0 THEN GOTO 1210 BEEP DISP ERROR STATUS IS S CLEAR Tims t t MEM LOCAL 7 GOTO 1370 DISP ERROR TIMEOUT ON THE HP IB BUS i END 2 19 HP h9h5A HP IB Operation Do a serial poll Is bit h of the status set Then data is available Read in a piece of data and return with it I
91. P 4O45A in the lockout state if REN is true If REN goes false the device goes local immediately All devices are removed from local lockout and returned to local The remote message for all devices is cleared A device sends this message any time it needs some type of interaction with the controller The message is cleared by the device s status byte message if it no longer requires service The HP 4945A sets the Service Request line SRQ true when it requires service 5 11 HP 4OL5A HP IB Operation Table 5 2 HP IB Messages and HP 4945A Responses con t Status Byte Serial Poll Parallel Poil Configure PPC Parallel Poll Enable PPE Parallel Poll Disable PPD Parallel Poll Unconfigure PPU Parallel Poll Listen Address LAD Unlisten UNL Talk Address TAD Untalk Command UNT Status Bit Definition and Response A byte that represents the status of a single device One bit indicates whether the device sent the required service message and the remaining seven bits indicate the opera tional status defined by the device This byte is sent from the talking device in response to a serial poll operation performed by the controller The HP 4945A sends its current status on the data bus Puts module into a state where parallel poll response may be programmed If the last command was the parallel poll configure programs the parallel poll response If the last command was the parallel
92. P IL capabilities AAL AH CO D DDO DC2 DTO Li PDO PRL RL2 SH SR1 T1 thru T HP IL DEVICE FUNCTIONS Automatic Address Acceptor handshake No controller capability Driver No device dependent commands implemented Full device clear implementation No device trigger capability Listen and unlisten if talk addressed No power down capability Complete parallel poll ability Receiver Full remote local capability Source handshake serial poll capability Full talker capability HP 4945A HP IL Operation Information is transfered on the HP IL from one device to another in quantities The loop messages and module response to the message are listed in called messages table 6 1 6 5 HP LOUSA HP IL Operation Table 6 1 HP IL Loop Messages and Module Responses Message Response Interface Clear IFC Unaddresses the module Data sustained in queues is retained This command must be sent when there has been a time out error SDC selected device clear or DCL device clear returns the HP h9h5A to this state Menu set Up Frequency 1004 Hz Display Level Envelope Delay in 4O44A mode TMT RCV Imp 600 ohms RCV Term Hold coils Off SF skip Off Voice limit Off Master slave Off Master to slave Talk battery Off Self check Full Mode 1 Segment 1 Stop on end check Noise Noise with tone C msg filter in 60 Hz filter out Sweep Stopped single from 204 to 3904 Hz Step 100 Hz
93. Path 1 1000 Hz 1000 10 1 e 18 5 dBm 18 5 T 3 Not Used 4 800 Hz 800 10 2 5 3 0 dBm 2 6 1200 Hz 3 T 3 0 dBm 3 8 2000 Hz 4 9 13 0 dBm 10 thru 16 not used A 17 HP HOSA Operating Verification Diagnostics Mode 11 MODE 11 Wideband Filter Calibration A1 A2 A4 A12 A17 A gain constant is generated for the PAR Program and C message filters on A2 The Al7 test signal ST17 is routed through the appropriate A2 filter except for data segment 4 through the Al wideband autorange and then to the FWA detector A reference measurement is made with no A2 filter to determine the absolute level variation This reference value is subtracted from all filter measurements The measured A2 filter constants are stored in non volatile RAM on the Al board Note This mode is a calibration only mode and not intended for troubleshooting Mode 12 provides more information if one of the filters fail If mode 11 fails mode 12 should also fail Following is a summary of the Mode 11 tests Results Data Displayed Segment Should Be Path 1 1004 Hz O dBm 600 PAR 0 0 1 0 2 1004 Hz 0 dBm 600 PRGM 0 0 1 0 2 3 1004 Hz 0 dBm 600 CMSG 0 0 1 0 3 4 1004 Hz 0 dBm 600 0 0 1 0 4 5 thru 16 not used A 18 HP lol5A Operating Verification Diagnostics Mode 12 MODE 12 A2 Filter Sweeps A2 A4 A5 A17 This mode does an abbreviated sweep of the A2 filters The transmitter signal from A17
94. R ded ue EAE E rs Ser HP IB Device PURCts Ons ue esca oo ade rue os DS S Guise uh aaa 5 8 Hessase eE i Eet edd axo meth eR at Mae ew etw ohh wd hi E P 5 9 serial poli Opera tions 2 c v eoe RR RARUAOR A ritu wo ses plo v aed 5 14 Controlling the HP HP NOuSAs N a sak oo RARE en nen 5 16 Example Program When Using the HP 9816A HP 9826A or HP 9836A 5 16 vi HP IL OPERATION STEEL OGG FO A ne ae ale en 2 6 1 Norm l Molere presei aed e wal adus oot Succ igor ag aid sud erdt edt p Ls 6 1 TRIER On I MOdG qnod owed o M Ra eta oA ee uai ee c dL ue Re 6 1 BES UD Ce ON a re e ps a een Biase bok ed she 6 1 Description susanne piu EN EEE TEEN 6 1 Instal AUTON en ee ee iut Ert La Ee Sake 6 2 Select Code ABAG SS S LocV aaepe a tacta rao teehee Be aS 6 3 Communication Ca pai I Lit ae wou Wave ew ay cede Puer dcs SEO qi 6 3 Data Input and Output Modes arresi erue RR PRENEZ 6 4 HP Ib Device Functions ls esed pecia er Sages ah ma t ee 6 5 Persae Poli OpShat Petits a e vx PV Ee DEED RO eR use c 6 9 Parallel Poll Operati neds ee Na RUF Rae obi boa cuca 6 9 Using the HP 41C as the Controller een 6 10 Sample Program Using the HP 41C Voiceband Frequency Run 6 10 VI RS 232C OPERATION PISCE OCUCT PON ys arava eee TTE rcu Set acne le hehe 1 1 SDORULIOSL LORS Dope re pf est Sua e ord er Oo Rata Salad aie dia ca Gao eins 1 1 MOS On Lat UO o s sir LEN Vd A CH aiid e D Ud ied PES PEE Zur 7 1 PUT DUP Leo a ee ee ed ee ean
95. RECEIVER NOISE TO GROUND TO FILTER AND DETECTOR Figure 4 10 Noise to Ground Related to Message Circuit Noise h 11 HP 49h5A Measurement Principles TRANSIENTS MEASUREMENTS The 3 level impulse noise hits and dropouts mode measures the interfering effects of transients phenomena These transient phenomena can cause data transmission er rors and interruptions to data communication systems This measurement mode allows simultaneous detemination of impluse noise counts at three different thresholds phase hit counts gain hit counts and dropout count The simultaneous measurement of these transient phenomena allows the HP LYL5A to reliably differentiate between each of them impulse Noise Impulse noise is that component of the received noise signal which is much greater in amplitude than the normal peaks of the message circuit noise and that occurs as short duration spikes or burst of energy Studies by Bell Telephone Laboratories have shown that the impluse noise spikes have duration of less than one millisecond and that all significant effects of the noise spikes disappear within four mil liseconds Waveform b in Figure 4 11 illustrates a received holding tone or test signal that includes interfering impulse noise spikes The impluse noise measure ment allows determination of impluse noise count on a voice channel given a specified measurement period all are selectable on the HP Y49454 Customers initiating and ter
96. T Delay ze DLAY AVGLV DZRFR FRQCY STLVL STFRQ WARNG ENDST Delay and level zero DLAY RLLVL DZRFR LZRLV LZRFR FRQCY STLVL SIFRQ WARNG ENDST ENVELOPE DELAY con t ro Pe USEC HEHE H DB one DEM 4 M4 xx HZ HAAN HZ waa DEM 4 4 EZ ZX 0 ro HH HH USEC HHH 3x DRM HHRMHH HZ FRrRHRH HZ 4H DBM te HH EH HZ XX 0 HH HK USEC s DB Xx Xx HZ nr DBM HR HHH HZ KH HHH HZ HER DBM SH HH HZ XX 0 HP 445A I O Module Codes Delay Relative level Level zero reference level Level zero reference frequency Frequency Status field level Status field frequency Warning message Highest priority End of set Delay Average level Delay zero reference frequency Frequency Status field level Status field frequency Warning message Highest priority End of set Delay Relative level Delay zero reference frequency Level zero reference level Level zero reference frequency Frequency Status field level Status field frequency Warning message Highest priority End of set INTERMODULATION DISTORTION Four tone no noise correction RCVST 2 NCFMS O NCFSD DB SCDPR DB NCFTD 35 DB THUPR DB AVGLV DBM STLVL DBM WARNG XX ENDST 0 Receive status four tones Noise correction factor message not corrected Noise correction factor second order Second product Noise correction factor third order Third product Average level tatus field level
97. T OUTPUT SEQUENCES These are the result strings in the order in which they may be expected for each of the measurements that the HP 49U45A makes where represents a numeric character LEVEL FREQUENCY No level zero AVGLV DBM Average level FROOCY Fr eee NZ Frequency STLVL DBM Status field level STFRO etre Ho Status field frequency WARNG XX Warning message Highest priority ENDST 0 End of set 8 4 LEVEL FREQUENCY con t With level zero RLLVL DB LZRLV DBM LZBER Ute go FRQCY 3X Xx xG Hz STLVL FM DEM STFRQ RHR MH HZ WARNG XX ENDST 0 NOISE WITH TONE NOTCH STLVL STFRQ WARNG ENDST SIGNAL TO SG NS STLVL STFRQ WARNG ENDS NOISE NOIS SILVL WARNG ENDST DBRN HHH DBM KHEAHKH HZ XX NOISE a DBM RM HHH HZ Xx 0 DBRN we DBM XX 0 NOISE TO GROUND NSTOG STLVL WARNG ENDST DBRN HH gt DBM AA e Relative level Level zero reference level Level zero reference frequency Frequency Status field level Status field frequency Warning message Highest End of set Noise with tone Status field level Status field frequency Warning message Highest End of set Signal to noise Status field level Status field frequency Warning message Highest End of set Noise Status field level Warning message Highest End of set Noise to ground Status field level Werning message Highest End of set 8 5 priority
98. TOP to manually stop the test A T HP 4945A Operating Verification Diagnostics Mode 1 MODE 1 Detector Digital and ADC Check A5 This mode checks the digital circuits and the analog to digital converter on the A5 Detector board The first six segments verify the digital circuits around the analog to digital converter and measure the time period of the A5 calibration signal The last five tests check the accuracy of the analog to digital converter and the functions of the detector multiplexer switch Following is amp summary of the Mode 1 tests Results Displayed Should Be 1 Board Presence Test 2 Walking Ones Test 3 not used T Comparator Tests 3 5 not used 6 Tracking ADC Tests 4 T Peak Detector Tests 5 8 Cal Signal Digital Tests O 0 6 9 Count Up Period Test 4096 20 6 10 Count Down Period Test 4096 20 6 11 not used 12 Tracking ADC Accuracy 188 18mV 7 13 not used 14 Voltage Reference Test 909 11 mV 8 245 not used 16 Receiver 5 0 V CLN 5000 250 9 A 8 HP h9l5A Operating Verification Diagnostics Mode 2 MODE 2 Detector Calibration Check A5 This mode calibrates the A5 detectors and then checks the calibration constants against known limits check of the A5 analog circuits is also done Each detector s input output characteristic is a linear function with slope and intercept values The dc offset refers to the intercept and the gain constant refers to
99. Taik Only Mode When the module is in talk only I O output mode pressing the output key on the front panel will cause an image of the display to be sent out on the interface to a printer which must be in listen always mode HP 4944A Mode When the module is in this mode it responds to all of the two character mnemonics used by the HP h9NlhA All data returning to the controller will be sent in the format used by the HP h9hhA which is an image of its display SPECIFICATIONS Dimensions Height 33 mm 1 32 inches Width 99 mm 3 91 inches Depth 1880 mm 7 12 inches Maximum Cable Length 20m 65 feet Operating Temperature O to 50 C 32 to 4122 F Storage Temperature 40 to 75 C hO to 167 F Power Requirements Supplied by HP 4945A Do not install interface with power on Operating power must be off OTL HP h955A HP IB Operation INSTALLATION The HP 18162A Interface connects to one of the I O slots on the HP h9h5A rear panel An HP IB cable connects to the other HP 18162A connector as shown in figure 5 1 WARNING The HP 4945A operating power must be off Do not install interface with power on The interface receives its power from the HP 4O45A No external power source is required HP 1B CABLE HP 18162A HP 4945A Figure 5 1 HP 181624 Interface Installation HP hoh5A HP IB Operation DESCRIPTION The HP IB is a parallel bus of 16 active signal lines grouped into three sets ac cording to
100. The AM process produces a signal whose spectrum consist of the carrier frequency plus an upper sideband fc fm and a lower sideband fe FM Figure 4 17 illustrates this relationship Since the upper sideband is of a higher frequency than the carrier it undergoes a greater phase shift than the carrier since the lower sideband is of a lower frequency it undergoes less phase shift _ 720 720 wu ues a E 9 S z a m D 3 360 360 5 g a 9 SS te Qe me n ie ut 300 1800 3000 300 1800 3000 Frequency Hz Frequency tHzi ia Ideal Linear Phase Characteristic tb Practical Nonlinear Phase Characterisac Figure 4 15 Phase Versus Frequency Relationship h 21 HP h9l5A Measurement Principles a Carrier Frequency fe b Modulating Frequency fm ici Resultant Amplitude Modulated Signal 2 E 5 lt idi Envelope of Waveform lc measured in microseconds Envelope This time difference Delay m MENU a ANC S CR Deiayed Envelope Figure 4 16 Envelope Delay Waveforms 4 22 HP h9h5A Measurement Principles If the AM signal is passed through a circuit having a phase shift characteristic which increases linearity with frequency figure 4 15 the envelope of the AM sig nal experiences a shift in time or delay as shown in waveforms d and e of Figure h 16 This occurs because the lower sideband experiences less phase shift than the carrier whi
101. The HP h9hl5A will automatically display the signal to noise ratio Noise to Ground Press the NOISE TO GROUND softkey 5 and observe the dBrn reading on the display Line Balance Calculation Ihe relative line balance of an end loop can be calculated by message circuit noise Nm and noise to ground Ng and applying the following formula Balance in dB Nm Ng Note This calculation is only valid if the measurements are made on a physical pair and if it is assumed that the message circuit noise is caused by longitudinal noise converted to message circuit noise by a line imbalance It is recommended that both of these measurements be made using the 3 kHz flat filter to account for the ef fects of power line related noise Noise With Tone Press the NOISE WITH TONE softkey 2 and observe the dBrn reading on the display 2 530 HP lh9h5A Operation TRANSIENTS Description The HP 49454 performs the following transient measurements Impulse Noise 3 level e Phase Hits Gain Hits e Dropouts The HP h9 l5A will also perform a noise with tone measurement and latch the results to aid you in setting the impulse noise thresholds The noise with tone measurement is always in progress whenever the transients measurement is STOPPED To enter the transients menu press the TEST SELECT hardkey and then the TRANSIENTS softkey 3 The following menu will appear 03 28 83 10 50 DEC Ed e START STOP TRANSIENTS
102. Transmission measurements on data circuits use test signals applied at data level the standard Bell System data level is 13 dBmO Data level is used to prevent overload on carrier systems Data level is a power 13 dB below the transmission level point TLP where the tests are being made For example at a 16 dB TLP the data level would be 29 dBm 16 13 29 A test power of 29 dBm would be applied here At the zero transmission level point 0 TLP the data level would be 13 dBm or 13 dBmO LEVEL AND FREQUENCY MEASUREMENTS The level and frequency mode allows measurement of 1000 Hz loss attenuation dis tortion and gain slope These measurements define the amplitude versus frequency response of voice channel The level and frequency mode also allows measurement of frequency shift Figure h 2 illustrates the basic setup for thse measurements TRANSMITTING TIMS RECEIVING TIMS 60 Hz FiLTER VOICE CHANNEL Figure 4 2 Level and Frequency Measurement 4 3 HP h9h5A Measurement Principles 1000 Hz Loss The 1000 Hz loss measurement determines the point to point loss or gain of a 1000 Hz test tone transmitted over a voice channel To make this measurement a 1004 Hz test frequency is transmitted at data level At the receiving TIMS th e received power is measured in dBm and substracted from the transmitted level to determine 1000 Hz loss in dB The transmitted frequency is actually 1004 Hz not 1000 Hz to prev
103. VEL hardkey Note All transmission measurements should be made at Data Level The Data Level for data circuits is a power of 13 dB below the Transmission Level Point TLP For exan ple if the TLP is 16 dB the Data Level would be 29 dBm Therefore an output level of 29 dBm would be ap plied in this case When requested by the receiver operator press the CHECK SIGNAL softkey 1 This will transmit the check signal for 12 seconds Each press of this key will add an additional 12 seconds to the transmission time General instructions Receiver I s Press the TEST SELECT hardkey Press the IMD NLD softkey 5 The IMD menu will be displayed Instruct the transmitter operator to send the check signal When this is in progress the status line of your display will read RCV CHECK SIG in Area 5 When it is done the message NOISE CORRECTED will appear on your screen This indicates that the data is now automatically corrected for noise Observe the readings on the display Note that the 2nd and 3rd order products are displayed in dB relative to the SIGNAL LEVEL 3 43 HP 4O45A Operation Master Slave Operation The instrument will automatically alternate between the CHECK SIGNAL and the IMD Signal Therefore the CHECK SIGNAL softkey 1 will be blank when in master slave operation 3 44 HP h9h5A Operation JITTER Description The HP 4945A performs both amplitude and phase jitter measurements in three d
104. WA wideband detector Be sure to run Mode 2 detector calibration before running this mode If inconsistent calibration data is used e g default calibration constants this mode is sensitive enough to have errors occur This sensitivity is due to the fact that the A7 output signals route directly to A5 with no autoranging done Following is a summary of the Mode 19 tests Data Results Displayed Segment Should Be T e 12 13 14 15 16 NOTE If the entire Mode 19 is run the results listed in the previous 3 through 6 are run individually the results displayed will be approximately 10 dB This is because when these segments are run individually table down 6 6 2 0 dB 10 3 2 0 dB 0 0 0 5 dB 6 0 1 0 dB 5 0 1 0 dB 13 25 1 5 dB not used 03 2 5 dB 3 5 1 0 dB 3 5 1 0 dB not used 0 12000 0 usec 3000 30 usec 3000 30 usec 3000 30 usec 3000 30 usec Transmit EDD CAL 41 75 Hz 41 75 Hz 41 0 Hz 42 25 Hz 40 75 Hz 2000 Hz 1845 Hz 2166 Hz ED A kHz ED 1 kHz ED 1 kHz ED 1 kHz ED 1 kHz should be displayed If Diagnostics Mode 19 Signal 9 0 2 0 0 0 34 dBm 600 3h dBm 600 34 dBm 600 0 0 0 0 0 segments dBm 600 aBm 600 dBm 600 dBm 600 dBm 600 dBm 600 dBm 600 dBm 600 dBm 600 dBm 600 dBm 600 HP h9h5A Operating Verification Test HI Q CAL
105. air and the transmitter and receiver connected to that pair 3 68 HP h9h5A Operation No Answer Received From Slave H 02 When During link up or re link only Pilot tone Yes Data No Direction of Test Either direction Problem Channel Either channel Additional Comments When you receive this message you are receiving the pilot tone back but not any data This message is only displayed during the linking process Data Errors In Slave Response H 03 When Anytime Pilot Tone Yes Data The data received has parity and or framing errors Direction of Test During Link up Either After Link up M S only Problem Channel If it occurs during link up then either channel may be causing a problem After link up has taken place the error is being caused on the communications channel Additional Comments In this case we are receiving data back from the slave but it contains parity and or framing errors Bad Data In Slave Response H 04 When During link up or re link only Pilot Tone Yes Data Yes Direction of Test Either Problem Channel Either Additional Comments This error will occur if the master receives a negative acknowledge NAK a bad block of data or the incorrect response from the initial inquiry sent to the slave unit 3 69 HP 4945A Operation Incorrect Response From Slave H 05 When During link up or re link only Pilot Tone Yes Data
106. ally by the HP 4945A Pressing the SIGNAL TO NOISE softkey will display the signal to noise ratio Response dB Tr DEZ LL Id UL Ll Frequency Hz Figure 4 9 Notch Filter Characteristic 4 10 HP h9h5A Measurement Principles NOISE TO GROUND MEASUREMENT The noise to ground mode allows measurements of the longitudinal noise present on a voice channel with reference to ground The transmitting TIMS provides a quiet termination at one end of the voice channel and the receiving TIMS provides a frequency weighted filter and detector at the other end The basic measurement technique for the noise to ground measurement is very similar to the message cir cuit noise measurement The main difference lies in the use of a ground reference Figure 4 10 illustrates this difference Noise to ground measurements are usually made for troubleshooting purposes and to measure the magnitude of longitudinal signals which may indicate the susceptibility of a cable pair to electrical coupling from external sources The relative line balance of an end loop can be calculated by substracting the mea sured noise to ground Ng value from the measured message circuit noise Nm value It is recommended that both message circuit noise and noise to ground be measured with the 3 kHz flat weighted filter to include the effects of power line related noise TRANSMITTER RECEIVER MESSAGE CIRCUIT NOISE QUIET i TO FILTER TERMINATION AND DETECTOR
107. alpha register Program frequency sk for a set of data Need dB in tenths Relative level Put it in the print buffer Justify into columns right and left Level zero reference level Level zero reference frequency Frequency Append it to the print buffer And print the line Status field level Status field frequency Warning message To Y register Load X register with 0 X not equal Y Then error occurred End of set Loop 37 times get data from 37 frequencies 304 Hz to 3904 Hz Do three linefeeds Go back to local control End of program 6 11 End of program m AUO TITTEN TT UNDU 10 NAL 0 CTI INN 6 12 JULIAN NNOO AL 1 A UUAN AUN 10 100 ANO nn 100 JEUDI HP LOUSA RS 232C Operation CHAPTER VIL RS 232C OPERATION HP 18163A INTRODUCTION The HP 18163A RS 232C Interface allows the HP 4OL5A to be controlled remotely from an external device that is configured for RS 232C serial communication Figure 7 1 shows the interface installation The HP 18163A Interface communicates asynchronously with external devices and is configured as a DTE Data Terminal Equipment SPECIFICATIONS Dimensions Height 33 mm 1 30 inches Width 99 mm 3 90 inches Depth 180 mm 7 09 inches Operating Temperature 0 degrees to 50 degrees C 32 degrees to 122 degrees F Storage Temperature 40 degrees to 75 degrees C hO degrees to 167 degrees F Power Requirements Supplied by the HP 4Q45A Do not
108. an be exited by sending mnemonic OFE Note Echo Lockout and Direct Control Mode are exited if power is cycled Local Lockout When the ONL command is sent to the interface front panel inputs and inputs from another interface are locked out The lockout is disabled by sending the OFL command STATUS REPORTING When an error is detected a request for sevice message is displayed just above the menu line The RS 232C interface does not have a serial poll or service request mechanism When an error in operation is detected by the I O module a corresponding bit is set in the status register The controller can read the status of the reg ister by sending an OE command The status is then sent in decimal to the con troller The decimal value and the meaning of the error bits are listed below Decimal Value Bit No Meaning 0 0 Invalid keycode error T 1 Locked out by other I O module 4 2 Initial link in progress or in slave mode 8 3 Front panel accessed 16 4 Overrun error 32 5 Parity error 64 6 Framing error HP h9h5A RS 232C Operation Any OR combination of 8 bits are possible The format of the status string is STSWD ddd CrLf Where ddd is amp three digit number When there are fewer than three digits leading spaces are inserted Example STSWD O0 CrLf The status word is reset to zero everytime it is read CONTROLLING THE HP 4945A Commands can be sent from the controller to the HP 4945A to control the HP 4oh5A s
109. and the input of commands These commands are the OUx commands The OUO command is a mask service request when data is available command The Ready bit in the serial poll register is set when there is data ready and reset when there is none This is the default state of the interface The OUl command will cause the I O module to make a service request when it has data available for the controller Both the service request and the Ready bit in the serial poll register will be reset when the output queue empties unless there was a previous error in which case only the Ready bit will be reset The OU2 command causes the module to hold off the HP IB bus handshake after the line feed following a command string from the controller until all mnemonics have been decoded and accepted by the HP 4Gh5A This is the default state of the module The OU3 command causes the module to release the data handshake on the HP IB bus as soon as the mnemonic commands have been received This mode enables parallel operation of many instruments without waiting for each to accept the codes before programming the next When using this mode it takes one to two seconds for each mnemonic to be decoded and accepted For example in an application where the HP 4O4SA transmitter is being used and an other TIMS receiver is being used to make the reading the transmitter output may not be the expected value if there is insufficient delay before the reading 25 2 HP
110. anked in master slave mode 2 This softkey establishes a zero reference at the current level reading 3 This softkey establishes a zero reference at the current delay reading h In master slave mode this softkey is labelled LEVEL FREQ DATA ON This fea ture allows you to choose whether or not to view the slave s level and frequency readings If you do not have a need to view this data set the softkey to OFF By choosing not to view the remote readings the measurement cycle is signifi cantly faster 5 Not Used 6 Not Used 7 Not Used 8 This softkey accesses the programmmable frequency sweep menu 3433 HP h9h5A Operation To set up a programmable frequency sweep when making the envelope delay measurement ment press the PROGRAM SWEEP softkey 8 The menu is shown below with explana tions of each of the selections After setting up softkeys 2 through 6 to the ap propriate settings start the sweep by pressing softkey 1 until it reads SWEEPING in parentheses 09 28 83 10 52 RH u START STOP PROGRAN SWEEP STOPPED DS NONSTOP DELAY 4312 USEC SWEEP RCY LEVEL 13 0 dBm SWEEP FROH 300 Hz SWEEP TO RCV FREQUENCY 1804 Hz 3400 Hz STEP SIZE 100 Hz STEP RATE SLOW Figure 3 19 The Programmable Sweep Menu for Envelope Delay Distortion 1 This softkey starts and stops the sweep It toggles between STOPPED and SWEEPING 2 This softkey toggles between SINGLE and NONSTOP NO
111. ase between the upper and lower sidebands of the AM signal superimposed on the phase characteristic plots Figure 4 18 Relating Phase Shift to Envelope Delay 4 24 HP 4OLSA Measurement Principles TIMS TIMS NORMAL SET REPEAT SET TRANSMITTER RECEIVER AND DISPLAY CARRIER OSCILLATOR 200 65004 Hz CIRCUIT AM UNDER TEST MODULATE 83 1 3 Hz OSCILLATOR MEASURE LEVEL AND CARRIER FREQUENCY 83 1 3 Hz AM PHASE DEMODULATE AM DEMODULATE 83 1 3 Hz COMPARATOR 83 1 3 Hz RETURN REFERENCE CIRCUIT MEASURE MEASURE FREQUENCY LEVEL CARRIER OSCILLATOR AM Remains Fixed MODULATE Nominaily 1800Hz DBM 2003 1800Hz 15 3 MICRO SEC RCV Hz 504 TRMT Hz LEVEL RECEIVER AND DISPLAY TRANSMITTER Figure 4 19 Envelope Delay Measurement 4 25 HP h9h5A Measurement Principles In the repeat set the demodulated AM signal is used to amplitude modulate the fixed frequency carrier that is transmitted back to the normal set The carrier oscillator in the repeat set remains fixed at one frequency during the envelope delay measure ment The carrier frequency is usually selected at midband normally 1800 Hz because envelope delay characteristic are fairly constant and attenuation distortion characteristics are fairly flat Because a constant return reference carrier frequency is used by the repeat set there will be no envelope delay distortion en countered by the return signal although there will be a fixed envelo
112. c power supply of the master oscillator of long haul carriers Some phase jitter can also occur in short haul systems form incomplete filtering of image sidebands The most commonly found frequency components of phase jitter are 20 Hz ringing current 60 Hz commerical power and the harmonics of these A bandwidth of about 800 Hz cen tered about a carrier near 1 kHz will recover the major suspected phase jitter without incurring large amounts of uncorrelated interference To measure phase jitter a 100l Hz holding tone is transmitted at data level At the receiving end of the voice channel is the test set configured to measure phase jitter Figure h 1ha illustrates the receiving TIMS functional configuration The received signal passes through the 600 to 1h00 Hz band pass filter This filter re duces the effective measurement bandwidth to approximately one fourth the total channel width centered on the test tone frequency This in turn reduces the effects of noise and other interference on hte jitter measurement The phase locked loop will not follow fast phase changes that occur at a rate greater than 20 Hz The slow response amplifier will not react fast enough to change the oscillator frequency to match the received frequency Fast phase change will cause an error to be generated by the phase detector The error signal appearing after the 300 Hz low pass filter is limited in frequency between 20 Hz and 300 Hz This pass band is a Bell Standa
113. crosstalk of multifrequency signaling for example do not fall in this category Single frequency tones may interfere with certain data signals particularly narrowband signals which are multiplexed onto a voiceband channel 4 6 HP 9h5A Measurement Principles A simple audio monitoring arrangement will usually detect this interference since tones exceeding acceptable levels are easily heard if the C message noise is within limits The single frequency interference check is made vith the set up as shown in Figure 4 3 After the receiver noise signal passes through the C message filter the resultant signal is applied to the line monitor speaker The TIMS operator listens for any predominant tone which may indicate a single frequency interference problem 1f a single frequency tone or tones of long duration is heard single frequency interference may be present and should be measured To precisely determine the frequency and level of the interfering tone a frequency selective voltmeter or spectrum analyzer must be used The requirement for single frequency interference is that when measured through a C message filter it will be at least 3 dB below C message noise limits D 2 2 e t e a L4 c Frequency Hzl Figure 4 4 C message weighting characteristic 1 4 7 HP h9h5A Measurement Principles Response dB 3000 4000 6000 Frequency Hz Figure 4 5 3 kHz Flat Filter Weighting Characteristic
114. d Impulse noise low Echo return loss Singing return loss high Singing return loss low Delay zero ref frequency low Level zero ref frequency low Level zero reference level HEADER STFRQ STLVL NOIS NSTOG NOTCH SG NS PAR SINRL RLLVL DLAY SCDPR THDPR STFRQ MDNUM DPOUT GNHIT PHHIT IMPHI IMPMD IMPLO CHORL SRLHI SRLLO DZRFR LZRFR LZRLV UNITS EZ DBM DBRN DBRN DBRN DB P AR DB DB USEC DB DB HZ CNTS CNTS CNTS CNTS CNTS HZ HZ DBM UNITS Also HP h9h5A I O Module Codes Table 8 1 Measurement Results and Headers cont d MEASUREMENT RESULTS HEADER UNITS Amplitude jitter 20 300 Hz PK Phase jitter 20 300 Hz DEG Amplitude jitter 4 300 Hz PK Phase jitter 4 300 Hz DEG Amplitude jitter 4 20 Hz PK Phase jitter 4 20 Hz DEG Transients running stopped Receive status l End of a set of data Noise correction factor second DB Noise correction factor third DB No of times self check passed Average level measurement fld DBM Frequency low measurement fld HZ Frequency high measurement fid HZ Level zero ref frequency high HZ Self check pass fail No of first test mode to fail Delay zero ref freg high HZ TLP Level status fld return loss DBMO No of segment being executed No of times self check has failed No of times self check has passed No of first test mode to fail Elapsed time minutes MIN Elapsed time seconds SE
115. d pass filter These signals are at a 775 Vrms level The level of each frequency is measured at ihe filter output to verify the filter performance Errors in the midband gain and errors in the filter shapes should show up as level errors Freguency errors indicate severe filter distortion or failure to pass the signal Following is a summary of the Mode 9 tests Results Data Displayed Segment Should Be Path 2500 Hz 2 0 0 dBm T 3 10000 Hz 10 2 u 18 0 aBm 2 5 not used amp 1200 Hz 1200 10 3 T 1 5 dBm 1 5 5 3 8 4800 Hz 4800 10 4 Q 21 0 dBm 21 1 lh 10 not used TT 500 Hz 500 10 5 12 30 0 dBm 30 2 5 13 1120 Hz 1120 10 6 1h 0 0 dBm 0 0 5 6 15 1600 Hz 1600 10 fi 16 9 0 dBm Q 1 T HP 955A Operating Verification Diagnostics Mode 10 MODE 10 Transmitter Alternate Channel Check A4 A8 A15 This mode connects the A15 self test signal directly to the Au input multiplexer A sine wave at 1000 Hz 775 Vrms is output through the alternate channel amp U305 and the 20 dB attenuator U505 in the transmitter s alternate channel Then the FSK low pass filter U405 is checked at three frequencies to insure proper attenuation of the mark and space frequencies as well as the high frequency roll off Any alternate channel problems should appear in at least one of the test paths Following is a summary of the Mode 10 tests Results Data Displayed segment Test Should be
116. d when the appropriate frequency tone is sent from A2 directly to the wideband autorange bypassing 43 For Data Segments 4 6 The 4 tone IMD signal at 40 dBm is routed through each of the IMD bandpass filter The signal then follows the usual IMD measurement path to the wideband autorange and RMS detector The result displayed is the negative value of the noise plus one for example 114 displayed is 115 dB 600 Following is a summary of the Mode 16 tests Results Displayed Should Be Filter 4 1 0 dB 520 Hz 0 0 dBm 600 520 Hz BPF 2 7 1 0 dB 1900 Hz 0 0 dBm 600 1900 Hz BPF 2 3 1 1 0 dB 2240 Hz 0 0 dBm 600 2240 Hz BPF 3 h 5 13 5 dB IMD 40 dBm 600 520 Hz noise 4 5 13 5 dB IMD 40 dBm 600 1400 Hz noise 4 6 13 5 dB IMD 40 dBm 600 2240 Hz noise h T thru 16 not used A 23 HP 4OLSA Operating Verification Diagnostics Mode 17 MODE 17 Jitter Digital and Phase Lock Loop Check A1 A6 This mode checks the communication path on A6 read write test The A6 A to D converter is also checked The phase lock loop lock time is measured and the capture range of the phase jitter phase lock loop is checked Following is a summary of the mode 17 tests Data Segment 1 1 0 11 12 13 14 15 16 Test Read Write Test 1 PASS O FAIL not used N A N A N A not used 20Hz PLL H
117. de any setup parameters associated with that measurement The Slave in turn will send back whether or not it has the capability to perform the measurement if not it will go into loopback mode and its level and frequency ranges for that measurement After the re link process is done the measurement takes piace Communication Pair vs Test Pair During the link up process communication takes place over both pairs as was dis cussed above When performing a measurement the test is being run over one pair which is referred to as the test pair The other pair is used for communication between the Master and the Slave In the Master to Slave direction the Slave will send back the measurement results over the communication pair In the Slave to Master direction the Master will be sending measurement commands to the Slave over the communication pair Communication is done using the FSK technique described earlier Envelope Delay Distortion Since the envelope delay distortion measurement requires four wires it is handled slightly different Following is a brief description of what takes place when in the Master Slave mode 3 63 HP 49454 Operation Master to Slave The Master sends an FSK signal requesting the Slave to per form a level and frequency measurement Next it sends the envelope delay signal using a variable frequency carrier The Master receives the cur rent level and frequency in formation performs the de
118. dence refer to instrument by model number and full serial number 2 3 HP h9l5A Operation CHAPTER HI OPERATION This chapter contains both general information about the instrument and specific information on how to use it for making measurements on your network Below is a brief synopsis of the main features of this chapter HP 4GLOA Features This contains front panel rear panel and display descriptions Data Entry Procedure Set This contains instructions on how to change the transmit level frequency or volume of the instrument It also covers changing parameters which are located inside a menu Up and Turn On Procedure This covers how to initially set up your instrument Some of the areas covered are termination impedance selection calibration hold coils and data time settings Measurements Each measurement is covered separately Each section contains a general description of the measurement menu and specific instructions on how to perform the measurement Following the measurements are instructions on how to use the OUTPUT hardkey to dump your results to a printer Also in this chapter is a brief description of all of the messages that appear on the display Master Slave The final section contains information on Master Slave It includes a descrip tion of what it is how it Works how to use it and all the error messages Also included are notes on operation when using an HP 4943A or an HP hONNA with
119. displayed only if the HP 4943A is making the phase jitter measurement and the reading is greater than 40 degrees Applicable only if using an HP 4943A or an HP h9hhA She HP h9h5A Operation Invalid Test Signal H 16 When After link up Pilot Tone Yes Data Direction of Test Either Problem Pair Either Aadi tionad Comments In certain measurements the instrument is able to detect if it is receiving the correct test signal These measurements are impulse noise IMD and the jitter measurements Unable To Complete M S Link When During initial link up or re link Pilot Tone Maybe Data Maybe Direction of Test Either Problem Channel Either Additional Comments This message is displayed if the instruments are unable to establish a link after a reasonable period of time You may not be receiving the pilot tone or data because of one of the other errors causing a problem Slave Not Capable When After link up Pilot Tone Yes Data Yes Direction of Test See comments below Problem Channel No Additional Comments This message will occur in two situations both when using an HP 4O4U3A or an HP hOhhA as a Slave The first is when you are set up in the Slave to Master direction of test and you try to change the Slave s transmit level The other situation is when you are set up in the Master to Slave direction of test and you try to change the impulse noise thre
120. e readings vary take the average General Instructions Forward Reference Repeat Test Set 1 2 Press the TEST SELECT hardkey Press the ENVELOPE DELAY softkey 4 The envelope delay menu will be displayed Press the NORMAL REPT softkey until REPEAT appears in parentheses Connect the pair to be tested to the TRMT terminals Connect the reference pair to the RCV terminals Adjust the output level to the Data Level using the LEVEL hardkey Note All transmission measurements should be made at Data Level The Data Level for data circuits is a power of 13 dB below the Transmission Level Point TLP For exam ple if the TLP is 16 dB the Data Level would be 29 dBm Therefore an output level of 29 dBm would be ap plied in this case 3 40 HP h9h5A Operation Adjust the transmit frequency to the reference frequency e g 1804 Hz or the frequency of minimum delay using the FREQuency hardkey Note The transmitter of the HP l9h5A is automatically set to 1804 Hz when the envelope delay menu is accessed Note If SF signaling units are used in the network under test SF SKIP should be ON refer to the Set Up Procedure Notify the normal test operator that you have completed step 6 When the Normal Test operator has notified you step 10 has been completed transmit the desired test frequencies using the FREQuency hardkey or the pro grammable sweep capability 3 41 HP 4945A Operation INTERMODUL
121. e can be located by observing the pattern of failures on the display Following is a summary of the Mode 4 tests including the attenuator and gain settings XMTR XMTR Wideband Results Data Output Course Fine Auto Amp Displayed Segment mV Atten Atten Gain Should Be 1 1199 10dB DaB 10dB 10000 100 2 12 99 DaB 10aB 10dB 10000 100 3 1199 20dB OdB OdB O 100 L 1199 10qdB 10qaB OdB O 4 100 5 1199 30dB 0B 10dB 10000 100 6 1109 20adB 10dB 10dB 10000 4 100 7 1199 LOdB OdB 20d0B 20000 100 8 1199 304B 10dB 20dB 20000 100 9 1199 504B OdB 30aB 30000 100 10 1199 hodB 10dB 30dB 30000 100 11 1199 60dB OdB 40dB 40000 4 200 12 1199 50aB 10qaB 104B 40000 200 13 1199 704B DaB 50dB 50000 2500 14 1199 60dB 10dB 50dB 50000 2500 45 1199 80dB OdB 604B 60000 10000 5000 16 1199 704B 10dB 604B 60000 10000 5000 HP 4945A Operating Verification Diagnostics Mode 5 MODE 5 Narrowband Autorange Amplifier Check A4 A15 A17 This mode checks the receiver fine attenuator and the narrowband autorange amplifier on Ad Following is a summary of the Mode 5 tests including the attenuator and gain settings AMTR RCVR Narrowband Results Data Output Course Fine Auto Amp Displayed Segment mV Atten Atten Gain Should Be 1 1199 10dB 0aB 10dB 10000 200 2 1199 OdB 10dB 10dB 10000 200 3 1199 20dB OdB OaB O 200 4 1199 10dB 10dB OdB 0 200 5 1199 30dB OdB 104B 10000 200
122. e clock no Time and date output format MO DY YR HH MM AM or PM or gt TRANSMITTER RECEIVER SET UP TRO Transmitter imp 135 ohms no TR1 Transmitter imp 600 ohms no TR2 Transmitter imp 900 ohms no TR3 Transmitter imp 1200 ohms no TR Reciever imp 135 ohms no TR5 Reciever imp 600 ohms no TR Reciever imp 900 ohms no TRT Reciever imp 1200 ohms no TRE Term no TRS Bridge no TRA SF skip off no TRB SF skip on no TRC Voice band limit off no TRD Voice band limit on no TRE Sleve transmit imp 135 ohms no TRF Slave transmit imp 600 ohms no TRG Slave transmit imp 900 ohms no TRH Slave transmit imp 1200 ohms no TRI Slave Recieve imp 135 ohms no TRJ Slave recieve imp 600 ohms no TRK Slave recieve imp 900 ohms no TRL Slave recieve imp 1200 ohms no TRM Slave term no TRN Slave bridge no 8 24 Mnemonic VOLUME PROGRAMMING VLO VL1 VL2 VL3 VL4 VLS VL6 VET VL8 VLO VLA VLB VLC ZERO FUNCTION Function Volume level Volume level Volume level Volume level Volume level Voiume levei Volume level Speaker off Speaker on Monitor receiver Monitor transmitter Keyboard beep off Keyboard beep on ONUT EWN RO Level zero Delay zero 05 Dy CA HP 4945A I O Module Codes Data Entry no no no no no no no no no no no no no no HP h9h5A Operating Verification APPENDIX A OPERATING VERIFICATION INTRODUCTION
123. e in conjunction with amplitude jitter measurements Amplitude jitter is measured in the Bell standard 20 to 300 Hz band the low frequency LF 4 20 Hz band and in the Bell standard plus LF 4 to 300 Hz band Fig ure h 1hb shows the functional configuration of amplitude jitter measurements 4 18 HP h9h5A Measurements Principles REFERENCE SIGNAL s Le PHASE JITTER a Effects of phase jitter on 1004 Hz holding tone PEAK TO PEAK AMPLITUDE JITTER 1004 Hz CARRIER b Effects of amplitude jitter on 1004 Hz holding tone Figure 4 13 Effects of Phase and Amplitude Jitter on Holding Tone 4 19 HP 4945A Measurement Principles PRASE LOCKED LOOP RECEIVE 400 1550 Hz AMPLITUDE PHASE 300 Hz MEASURE SIGNAL BAND PASS LIMITER DETECTOR LOW PASS AND FILTER n FILTER DISPLAY VOLTAGE SLOW CONTAOLLED RESPONSE OSCILLATOR AMP a Phase jitter measurement 600 1400 H2 FULL WAVE 20 H2 300 Hz MEASURE RECEIVED BAND PASS RECTIFIER HIGH PASS LOW PASS AND SIGNAL FILTER FILTER FILTER DISPLAY Amplitude jitter measurement Figure 4 14 Phase and Amplitude Jitter Measurements 4 20 HP 4ouSA Measurement Principles ENVELOPE DELAY MEASURMENT The envelope delay mode allows measurement of the linearity of the phase versus frequency of a voice channel Phase information has an insignificant effect on voice transmission but can seriously affect data transmission
124. eate errors by appearing like information carried by data signal For example in a system using an 8 phase modulation technique 45 degrees between states frequent 25 degree phase hits would make it very diffcult for the receiving modem to distinguish between the interfering phase hits and the phase modulation resulting in phase hits caused errors 4 12 HP h9h5A Measurement Principles A gain hit is a sudden change increase or decrease in the received signal level Gain hits can be less than a dB or as large as several dBs The level of the received signal can return to its orginal value in a short time or it can remain indefinitely at the changed value Waveform d in Figure 4 11 illustrates received holding tone that includes interfering gain hits Amplitude modulation of a carrier signal is another common technique used by modems to transmit data Because the information is contained in the level of the signal gain hits can appear like the information carrier by the data signal resulting in gain hit caused errors A dropout is a sudden drop in recieived signal level gt 12 dB During a dropout the signal often becomes undetectable Some dropouts are difficult to observe because the background noise can rise to a level near the orginal signal level The level of the received signal can return to its orginal value in a short time or remain undetectable indefinitely Waveform e in figure 4 11 illustrates a received holding tone t
125. echanically and electrically if the contents of the shipment is incomplete if there is nechanical damage or de fect or if the instrument does not pass the Self check and Performance Test notify the nearest Hewlett Packard office If the shipping container or the cushioning material shows signs of stress notify the carrier as well as the Hewlett Packard office Keep the shipping material for carrier s inspection The HP office will arrange for repair or replacement at HP option without waiting for claim settlement PREPARATION OR USE Power Requirements The HP 4O45A requires a power source of either 115 or 230 Vac 48 to 63 Hz single phase Maximum 150 watts Line Voltage Selection The voltage selector switch is located on the rear panel Verify that the switch is set to the local operating line voltage Also located on the rear panel is the line fuse Verify that the fuse rating corresponds to the line voltage Refer to table 2 1 for fuse rating and part numbers HP 4945A Installation Table 2 1 Line Fuse Part Numbers Line Voltage Fuse Rating HP Part Number 115 volts ac 2110 0381 230 volts ac 2110 0304 Power Cable This instrument is equipped with a three wire power cable When connected to an appropriate ac power receptacle this cable grounds the instrument cabinet The type of power cable plug shipped with each instrument depends on the country of destination l STORAGE AND SHIPMENT Environ
126. en the two instruments is transparent to the user The details of how it actually works and how to use it are contained in the following sections MASTER mansmuts test tones jest parr communication pair SLAVE sends measures results 10 MASTER for dispiay MASTER TO SLAVE direction MASTER sends commands to SLAVE receiver communication pair test pair SLAVE transmits test tones SLAVE TO MASTER direction Figure 3 25 Master Slave Test Set Up FSK Technique The two units communicate their information using internal lowspeed modems The modems employ a technique called frequency shift keying FSK to code the data going over the line They transmit 800 Hz to represent a space or a 0 and 1200 Hz to represent a mark or a 1 In addition a 1990 Hz pilot tone also referred to as the carrier is used to alert the receiving unit that FSK data is coming This is to prevent noise from being interpreted as data 3 62 HP 49454 Operation Direction of Test This term is only applicable when you are performing a measurement Direction of test refers to the direction that the measurement is taking place Master to Slave means that the Master unit will transmit the test signals and the Slave unit will receive them and perform the measurement Slave to Master is just reversed n easy way to think about it is to visualize the test signal moving in the direc tion that is listed Master to Slave mean
127. ent is now ready to print any display by simply accessing the display perform the measurement and then press the OUTPUT hardkey HP h9h5A Operation DISPLAY MESSAGES Following is a list of messages with their explanations It is divided by the area on the display where it occurs AREA 2 MESSAGES REMOTE This will be displayed in inverse video when a controller has control of the instrument REMOTE WITH LOCAL LOCKOUT This is displayed when a controller has control of the instrument and the keyboard is locked out SERVICE REQUEST Refer to chapter 5 6 or 7 NO HOLDING TONE In a measurement where a holding tone is used e g Jitter a oss of tone will cause the warning message NO HOLDING TONE to appear in inverse video Loss of Tone is defined as a receive level below 40 dBm or a receive frequency that is not between 995 1025 Hz IMD SIGNAL NOT RECEIVED In the intermodulation distortion measurement the receiver will check to see if a valid IMD signal is being received If not the above warning message will be displayed in inverse video NO MODULE HP IB RS 232 HP IL In the I O port set up menu the display will identify what module if any is piugged in NPD ORDER DIST NOISE lt 2dB 3RD ORDER DIST NOISE 2dB 2ND 3RD ORDER DIST NOISE lt 24B These messages indicate that the distortion level is within 2 dB of the background noise MASTER SLAVE WARNING MESSAGES Refer to the master slave sectio
128. ent measurement errors which would occur over T carrier systems This 4 Hz offset avoids measurement errors caused by test frequencies which are submultiples of the T carrieer sampling rate This measurement error is not representative of actual conditions which are present when multiplfrequency signals like voice and data are transmitted over voice channels The accuracy of the received power measurement depends on the tolerance of the receiving and resistive termination A terminating resistance of 0 1 percent tolerance is required to assure accurate measurements Therefore received level measurements should generally be made using the HP 4945A internal termination A switch selectable 60 Hz high pass receiving filter is provided for use with the level and frequency measurements The 60 Hz filter is used to detect and remove ex cessive 60 Hz interference The filter has an attenuation characteristic greater than 20 dB at 60 Hz and a 4 dB attenuation characteristic at 180 Hz 3rd harmonic of 60 Hz Frequency Shift The frequency shift measurement checks for any difference in the received frequency with reference to the transmitted frequency frequency translation as caused by carrier facilities To make this measurement a test tone of known frequency is transmitted At the receiving end the received frequency is observed and compared with the transmitted frequency Any difference between transmitted and received frequencies indicates a freq
129. ent with much higher resolution and accuracy than the standard measurement This mode evaluates the hardware software performance in measuring the P AR value The displayed results are in thousandths of a P AR unit Mode 51 Receiver Troubleshooting This mode can assist you in troubleshooting the receiver The receiver is used as a voltmeter and each path sets a different autorange amplifier gain so the autoranging is held at one static gain condition This is useful for checking detector linearity and signal path continuity Voltages are displayed if the detectors need to be checked Following is a summary of the Mode 51 tests Path Gain both amplifiers 1 10 dB 2 0 dB 3 10 dB LI 20 dB 5 30 dB 6 4oO dB T 50 dB 8 60 dB A 34 HP 49454 Operating Verification Diagnostics Modes 51 and 52 Following is a summary of the information displayed on the various display lines Display 1 XXXXXX rms voltage wideband channel 2 XXXXXX rms power wideband channel m XXXXXX average voltage wideband channel 5 XXXXXX rms equivalent power wideband channel T XXXXXX average voltage narrowband channel 8 XXXXXX rms equivalent power narrowband channel 10 XXXXXX peak voltage wideband channel 11 XXXXXX peak power in dBm wideband channel 14 XXXXXX peak power narrowband channel 15 XXXXXX peak power in dBm narrowband channel Mode 52 IMD Relative Tone Adjustment Level measurements are taken internally for
130. equencies as listed in Table 4 4 This type of distortion is termed intermodulation distortion or nonlinear distortion and is the type measured by the HP L954 o gt 2 T lt 1380 Frequency Hz Figure 4 20 Intermodulation Distortion Signal Frequency Sprectrum 4 27 HP h9l5A Measurement Principles Table 4 4 shows the harmonics of a multiple frequency signal f1 and f2 Table 4 4 Harmonies and Intermoduation Products of a Multiple Frequency Signal f1 and f2 TYPE OF OUTPUT DISTORTION DISTORTION THRU THE THIRD ORDER Harmonics 2f4 3f 2f 3f5 intermodulation fa fo t5 fa 214 fo Intermodulation distortion and harmonic distortion measurement techniques will yield the same value for second and third order distortion in the simple case involving only one source of distortion However with a telephone channel there are normally multiple surces of distortion joined together by linear networks with delay distor tion This creates measurement problems in obtaining valid distortion values Bell Telephone Laboratory studies have shown that the intermodulation distortion tech nique is less susceptible to these measurement problems The check signal provision is included in the HP 4945A to permit correction of error caused by the presence of high background noise an interferring tone or T carrier quantizing noise When the CHECK SIGNAL softkey is pressed the second tone pair shown in Fig
131. esigned with the Master Slave capability Each contains only a subset of the HP 4945A s measurements Also they have LED displays and their front panels have switches and knobs Due to these constraints they are unable to display error messages in plain English they display H codes and some of their switches are not programmable through Master Slave operation What is Loopback mode As mentioned before the measurement capability is limited when using an HP 49434 or HP hohhA When an HP 4943A or HP hOhlA is instructed to perform a function that is beyond its capabilities it will go into loopback mode This means that the incoming signal to the Slave will be looped around and sent back to the master at the level which has been set on the Slave unit To get out of loopback mode press a different key and the instruments will re link Configuration Considerations When Master is an HP 4943A or HP 49444 and Slave is an HP 4945A In this configuration the HP 4945A is limited to the capabilities of the Master Examples of these limitations are Frequency and level range limitations of the HP 4O43A or HP olla No amplitude jitter measurements No automatic gain slope measurement T counts sec in impulse noise No phase hits gain hits or dropouts measurements e 9 The following items must be set on the HP 49QU5A Slave before it is put into Master Slave mode transmitter and Receiver Impedances Transmitter and Receiver Hold C
132. etup Following is an example command line using BASIC as the programming language OUTPUT select code command data or Lf The command is a three character code that is translated into key sequences by the HP h955A Data is not required on all the commands The mnemonics and the function that enable the HP h9l5A to make each measurement are listed in Chapter VIII 7T HP HOLSA I O Module Codes CHAPTER Vill I O MODULE CODES INTRODUCTION This chapter identifies and lists the interface control codes and formats necessary for communications between the HP 49G4U5A and the following I Os HP 18162A Option 101 HP 18163A Option 102 HP 18165A Option 103 OUTPUT FORMAT TO THE CONTROLLING INTERFACE Each piece of data is preceded by a header and a space The numeric data as received from the HP 4945A follows the header and space This data may contain leading and trailing spaces depending on the data itself and the size of the responding data field in the display The numeric data is followed by the suffix which is the same as that displayed on the CRT with the following exceptions all characters are converted to upper case frequency is in units of hertz and the mu sign in microseconds is replaced with capital U The up and down arrows representing overrange underrange and unstable data are changed to numbers before outputting The UP arrow is replaced by 9 9E9 The DOWN arrow is replaced with 9 9E9 and the
133. f status is zero then everything is OK If bit 4 is not set and status is not O then error Clear the instrument Return it to local control Timeout routine HP h9h5A HP IL Operation CHAPTER VI HP IL OPERATION Model 181654 INTRODUCTION The HP 18165A interface allows an external controller to remotely control the HP 4O45A through the HP IL Hewlett Packard Interface Loop Normal Mode In normal operation commands from the controller are sent to the HP 18165A Inter face where they are converted into keystroke sequences to set up the HP h9l5A Data from the HP h9l5A is sent to the interface and then to the controller Taik Only Mode When the module is in the talk only I O output mode pressing the OUTPUT pushbut ton on the front panel will cause an image of the display to be sent out on the in terface to amp printer which must be in listen always mode SPECIFICATIONS Dimensions Height 33 mm 1 30 inches Width 99 mm 3 90 inches Depth 180 mm 7 09 inches Maximum Cable Length 10 m 33 feet between devices with standard cable Operating Temperature 0 to 50 C 32 to 122 F Storage Temperature LO C to 75 C 40 to 167 F Connectors Two pin Signal Level 1 5 Vac Power Requirements Supplied by HP 4945A The HP 9U45A operating power must be off Do not install interface with power on DESCRIPTION The HP IL is a two wire loop Communication over the loop is asynchronous and serial with digital
134. frequency carrier 300 to 6500h Hz and a fixed modulation frequency 83 1 3 Hz The carrier frequency is varied over the band of interest usually in 100 Hz steps The test signal traverses the voice channel under test and is received by the repeat set The receiver of the repeat set amplitude demodulates the incoming test signal to produce the AM envelope Changing the carrier frequency as mentioned above will result in a change in the delay of the 83 1 3 Hz envelope at the repeat set if envelope distortion exists The envelope delay values received at the repeat set must now be trasnmitted back to the normal set without the introduction of a chang ing envelope delay as would be introduced by changing the return reference carrier frequency amp E X Frequency Figure 4 17 AM signal frequency spectrum 4 23 HP 4945A Measurement Principles Phase Shift degrees Phase Shift degrees 0 300 1800 3000 1800 Frequency Hz Frequency Hz a Linear Phase Characteristic with Superimposed c Nonlinear Phase Characteristic with Superimposed AM Signal Components AM Signal Components 3000 Pse ort mr d mee 2000 3 amp E E v amp 5 2 1000 See a 1 104 i92 RE t l 300 1800 3000 7800 Frequency Hz Frequency Hz b Envelope Delay Characteristic of a above d Envelope Delay Characteristic of c above NOTE The symbol phi represents the difference in ph
135. function to interconnect up to 15 instruments Figure 5 2 is a diagram of the interface connections and bus structure One set of signal lines is the eight data lines These lines carry coded messages which represent addresses program data measurements and status bytes The data lines are used for both input and output messages in bit parallel byte serial form Normally a seven bit ASCII code represents each byte of data leaving the eighth bit available for parity checking There are three data byte transfer control lines Data transfer is controlled by means of an interlocked handshake technique that permits data transfer asynchronously at the rate of the slowest device participating on the bus There are five general interface management lines which are used to activate all the connected devices at once i e clear the interface Table 5 1 defines each of the management lines Table 5 1 General Interface Management Lines Mnemonic Description Attention Enables a device to interpret data on the bus as a controller command command mode or data transfer data mode interface Initializes the HP IB system to an Clear idle state by unaddressing all talkers and listeners Service Alerts the controller to a need for Reguest communication Remote Places devices under remote program Enable control End or Identify Indicates the last data byte in a data transfer sequence Used with AIN to poll devices for their status
136. goes through the A2 multiplexer U706 and through the selected filter The signal goes through the Ah wideband autorange and then to the FWA detector on A5 All measurements are made relative to data segment 1 Following is a summary of the Mode 12 tests All tests are done at a 0 dBm level and 600 ohm termination impedance Results Data Displayed Segment Should Be Test Filter Path 1 0 0 1 0 dB 1000 Hz No filter 1 2 3 0 1 8 dB 3000 Hz 3 kHz 2 3 12 3 3 0 dB 6000 Hz 3 kHz 3 4 3 0 1 8 dB 15 0 kHz 15 kHz h 5 Le ok F320 dB 30 0 kHz 15 kHz 5 6 1 1 1 0 dB 100 Hz 50 k bit 6 T 0 0 1 0 dB 1000 Hz 50 k bit T 8 8 3 2 0 dB 40 0 kHz 50 k bit 8 9 11 6 2 0 dB 300 Hz Program 9 10 0 0 1 0 dB 1000 Hz Program 10 11 T 2 2 0 dB 4000 Hz Program 11 12 16 3 2 0 dB 300 Hz C message 12 13 0 0 1 0 dB 1000 Hz C message 13 14 15 0 2 0 dB 4000 Hz C message 14 15 1h 1 1 0 dB 800 Hz P AR 15 16 3 0 1 0 dB 1526 Hz P AR 16 A 19 HP h9l5A Operating Verification Diagnostics Mode 13 MODE 13 A2 Filter Checks Continued A2 A4 A5 A17 This mode continues the A2 filter checks The signal is routed from A17 through A2 After passing through the selected filter the signal goes through the A4 wideband autorange and then to the FWA detector on A5 narrowband atutorange path is used Segment 1 Following is a summary of the Mode 13 tests termination impedance Data Segments 1 2 MO 10 11 12 13
137. hat includes interfering dropouts All communication crease during a dropout and data can be lost The receiving mode must re reference itself to the signal before data communication can resume Most modems can track the received signal to a level as low a 12 dB below their normal receiving power Beyond 12 dB the information signal is considered lost 4 13 HP 4945A Measurement Principles a Trensmitted Test Signal fb Received Test Signat n with impulse Noise Spikes ic Received Test Signal with Phase Hirs Amplitude id Received Test Signal with Gain Hits te Received Test Signal with Dropouts Time Figure 4 11 Impulse Noise Hits and Dropouts Waveforms 4 14 HP 4945A Measurement Principles Simultaneous Measurement of Impulse Noise Hits and Dropouts The relationship between each of the transient disturbances is summerized in table h 2 The best way to distinguish impulse noise from dropouts is the ms maximum duration of the impulse noise Phase hits can be distinguished from gain hits and dropouts because phase hits cause change in phase Dropouts have to be distinguished from gain hits by definition since dropouts are a special case of gain hits Table 4 3 summarizes the measurement definitions necessary for implementing a practical measuring instrument The information needed about each disturbance is how often they occur The measuring instrument is required to total each disturbances
138. he receiver input weighted by the appropriate filter The ac signal is measured for peak average or rms value The true voltage and power of the Signal are given These measurements assume ideal termination impedances within the receiver Only some of the detector readings are displayed Following is a summary of the Mode 9 tests Channel Filters Wideband Narrowband 1 Flat Flat 2 P AR P AR 3 1010 Hz notch Flat 15 kHz 4 50 kbit Flat 5 15 kHz Flat 6 3 kHz Flat T Program Flat 8 C message Flat 9 Phase Jitter Phase Jitter 10 IMD 520 Hz Flat 13 IMD 1900 Hz Flat 12 IMD 2240 Hz Flat 23 IMD notch Flat 1h 10 kHz LP 10 kHz LP 15 60 Hz HP 60 Hz HP 3 kHz 16 Flat Transients filter amp 33 HP hol5A Operating Verification Diagnostics Modes 49 50 and 51 Following is a summary of the information displayed on the various display lines play Pid Line Display 1 XXXXEX rms voltage wideband channel 2 XXXXXX rms power wideband channel l XXXXXX average voltage wideband channel ES XXXXXX rms equivalent power wideband channel T XXXXXX average voltage narrowband channel 8 XXXXXX rms equivalent power narrowband channel 10 XXXXXX peak voltage wideband channel 11 XXXXXX peak power in dBm wideband channel ku XXXXEX peak power narrowband channel 15 XXXXXX peak power in dBm narrowband channel Mode 50 Super P AR This performance mode gives you a P AR measurem
139. he TEST SELECT hardkey and then the LEVEL FREQuency softkey 1 The following menu will appear 09 28 83 10 45 AN LEVEL FREQUENCY GAIN SLOPE LEVEL ZERO RCY LEVEL 7 0 dBm gt n wa 60Hz FILTER RCY FREQUENCY 1004 Hz COUT Figure 3 12 The Level Frequency Measurement Menu 1 This softkey begins the GAIN SLOPE measurement 2 This softkey establishes a zero reference at the current level reading 3 21 HP h9h5A Operation 3 This softkey inserts a 60 Hz high pass filter in the receive path This attenu ates 60 Hz by at least 20 dB without affecting the holding tone 1004 Hz measurements 4 Not Used Not Used Not Used NO WV 1 Not Used 8 This softkey accesses the programmable frequency sweep menu To set up a programmmable frequency sweep when making the Level Frequency measure ment press the PROGRAM SWEEP softkey 8 The menu is shown below with explana tions of each of the selections After setting up softkeys 2 through 6 to the ap propriate settings start the sweep by pressing softkey 1 until it reads SWEEPING in parentheses 09 28 83 10 47 AM T START STOP s PROGRAM SWEEP STOPPED NONSTOP SUEEP RCY LEVEL 7 0 dBm o un SUEEP FROM RCY FREQUENCY 1004 Hz 100 Hz SUEEP TO 5 110 00 KHz STEP SIZE Jie C1000 Hz SET 5 SLOUD 7 8 Figure 3 13 Programmable Sweep Menu for Level Frequency Measurement 3 22 HP 4945A Operation This softkey starts and st
140. he external device sets Data Set Ready true when it is ready to send and receive data If Data Set Ready and Data Terminal Ready are not true no data transfer can occur as these lines mirror the status of the hardware To send data the module sets Request To Send true When the modem has control of the line it will set Clear To Send true and set Receive Line Signal Detect false The HP 18163A will begin to transmit data When the transmission is complete the module will set Request To Send false Request To Send will not be asserted again unless Clear To Send and Received Line Signal Detect are false Receive Line Signal Detect must be true and Request to Send must be false for data to be accepted Data Terminal Ready E and Data Set Ready ILIA E SEE Ree To Send eee We ee ee Clear To Send Received Line Signal Detect Transmitted data KEERN et ae valid Received data MORN valid SOFTWARE HANDSHAKE Besides the hardware handshake a software handshake may be used to control the flow of information For example in the common three wire configuration the hardware is assumed to be ready at all times and a software handshake is required The in terface uses either the ENQ ACK DC1 or the Xon Xoff DC3 handshakes The ENQ ACK handshake is called transmitter protocol because the transmitter is responsible for controlling the handshake The transmitter sends an ENQ when it wants to send a block of information Upon receiving an AC
141. he proper control settings for your application Tabie 3 1 Circuit Control Settings 2 Wire Wet DDD 2 Wire Dry Dial TRMT HOLO through OFF butt in RCVR HOLD OFF DIAL TALK ON TALK BAT OFF 4 Wire Dry TRMT HOLD TRMT HOLD Talk TRMT HOLD through OFF OFF OFF butt in RCVR HOLD RCVR HOLD RCVR HOLD OFF OFF OFF DIAL TALK DIAL TALK DIAL TALI ON ON TALK BAT TALK BAT ON ON TRMT HOLD TRMT HOLD Listen through OFF OFF butt in RCVR HOLD RCVR HOLD RCVR HOLD OFF OFF OFF DIAL TALK DIAL TALK DIAL TALK ON ON ON TALK BAT TALK BAT TALK BAT OFF ON ON TRMT HOLD TRMT HOLD TRMT HOLD ON OFF OFF RCVR HOLD RCVR HOLD RCVR HOLD ON OFF OFF DIAL TALK DIAL TALK DIAL TALK OFF OFF EE TALK BAT TALK BAT TALK BAT COFF OFF OFF Next press the TEST SELECT hardkey and proceed with the measurement Note The hold coils do not switch lines with the line reverse switch This is to prevent the line from being dropped 3 20 HP h9h5A Operation LEVEL AND FREQUENCY Description This section describes the following types of level and frequency measurements 1000 Hz Loss Measurement Frequency Shift Measurement Attenuation Distortion Gain Slope Measurement To enter the Level Frequency menu press t
142. hex written 55 hex code written to I O AA hex code not read back Status bit fails to go true after AA hex written AA hex written to I O 55 hex not written back HP 4OUSA Operating Verification DIAGNOSTICS The diagnostic checks allow you to verify the instrument operation If a faulty segment is found the instrument may still be functional for the other measurements To access the diagnostic modes see Table A 1 press the SETUP hardkey and then press the CALIBRATE SELF CHECK softkey You now have the choice to run all the diagnostic modes a specific mode or a specific path within a mode You can also specify the trigger condition on which the test can be stopped See Table A 2 To run all the modes select FULL SELF CHECK and then press START STOP To run a specific mode select MODE SELF CHECK press MODE and then enter the mode number from the keyboard and press ENTER Press the START STOP key to start the mode test fo run a particular path within a mode first select the mode and then select SEGMENT SELF CHECK Press SEGMENT and enter the data segment number associated with that path from the keyboard Press ENTER and then press START STOP to start the peth test Tabie A 1 Diagnostic Modes Mode Number Title 1 Detector Digital and ADC Check A5 2 Detector Calibration Check A5 3 Basic Transmitter Check A5 A15 4 Wideband Autorange Amplifier Check Ah A15 A17 5 Narrowband Autorange Amplifier Check A
143. ict Manager information American Telephone and Telegraph Co P O Box 915 Florham Park New Jersey 07932 INPUT OUTPUT SWITCHING The RECEIVE TRANSMIT JACKS provide for interconnection of the HP h9h5A to the cir cuit under test See Figure 4 1 The RECEIVE TRANSMIT switch provides for selection of either the transmit or receive function for the left jacks and simultaneously selects the opposite for the right jacks Both the left and right sets of jacks provide parallel connections the standard five way binding posts on top and the Western Electric 310 type jacks on the bottom Either the binding posts or the 310 jacks may be used they will not normally be used at the same time The hold current coil allows the application of a 23 mA current source to both the right and left set of jacks TIP and RING connections This allows for latching of telephone switching equipment Either the right or left set of jacks may be used for 2 wire dry circuit If a 4 wire circuit is under test the left jacks may be used for either transmit or receive and the right set for the opposite The transmit and receive impedance of the HP 4945A is selectable at 135 600 900 or 1200 ohms termination resistors figure 4 1 which are standard telephone circuit values The impedance of the test set must be selected to match the circuit under test or erroneous measurement values will be obtained The receive input may be terminated or bridged across the circuit unde
144. if ferent bandwidths They are 20 to 300 Hz Bell 4 to 300 Hz Bell Low Frequency and 4 to 20 Hz Low Frequency The jitter measurements can be made individually or using the measure all feature you can make both measurements in all three bandwidths sequentially To enter the jitter menu press the TEST SELECT hardkey and then the JITTER soft key 6 The following menu will appear RHPLITUDE JITTER CON PHASE JITTER ON 20 300 Hz AMP 0 0 x PK 20 300Hz 20 300 Hz PHASE 1 30042 IRCY TERMI 13 0 dBm 13 0 dBm Figure 3 21 The Jitter Measurement Menu HP l9h5A Operation lhis softkey enables the amplitude jitter measurement When it is ON the am plitude jitter measurement will be displayed in the selected bandwidths This softkey enables the phase jitter measurement When it is ON the phase jitter measurement will be displayed in the selected bandwidths This softkey selects jitter in the 20 to 300 Hz banduidth This softkey selects jitter in the 4 to 300 Hz bandwidth This softkey selects jitter in the 4 to 20 Hz bandwidth This softkey selects the desired jitter measurement in all three bandwidths Not Used Not Used General Instructions Transmitter Same for both amplitude and phase jitter ia 2 3 Press the TEST SELECT hardkey Press the JITTER softkey 6 The Jitter menu will be displayed Note The transmitter of the HP H9hl5A will be automatically set to 1
145. it is ready to receive data sent by the active talker device Talker A device with talker cabability that is talker active As such it is ready to send data to one or more active listeners There can only be one device acting as a talker at a given time System Controller At power on only one device on HP IL can assume the role of system controller The system controller resets the loop at power on and becomes controller active The system contreller can reset the loop and become controller active at any time even if control has been passed to another loop device The HP 4945A can not be system controller Controller Active The controller active device configures the loop for the ex change of data by sending commands that designate one talker and one or more lis teners It can also send commands to cause specific actions to occur within a device such as a test setup or clear The controller active device may be able to pass control to any other loop device capable of receiving control Serial Poll The controller active device can serially poll another device to ob tain its status byte The status byte denotes the device s present status and Whether or not it requested service Parallel Poll The controller active device can conduct a parallel poll to obtain a status bit from devices on the loop that are properly configured 6 3 HP 4Q45A HP IL Operation DATA INPUT AND OUTPUT MODES There are four commands that control
146. ity End of set Echo return loss Low singing return loss High singing return loss Status field level Warning message Highest priority End of set Sine wave return loss Status field level Status field frequency Warning message Highest priority End of set Echo return loss Status field level Warning message Highest priority End of set Low singing return loss Status field level Warning message Highest priority End of set 8 12 HP 195A I O Module Codes RETURN LOSS 16 TLP con t High singing SRLHI fw TLPLW o WARNG XX ENDST 0 Measure CHORD eU SRLLO Wes SREHI est TLPLV HEH OX WARNG XX ENDST O SELF CHECK NUMPS T2 NUMFL er MDNUM zz PATH 1 LN 1 LN 2 PATH 2 LN 2 PATH nn DB DBMO DB DB DBMO RH RH PASS HHKK GK FAIL FERNEN PASS Figh singing return loss Status field level Warning message Highest priority End of set Echo return loss Low singing return loss High singing return loss Status field level Warning message Highest priority End of set Number of times self check has passed Number of times self check has failed Number of mode being executed is zz Number of segment being executed 1 Each segment has at least one and sometimes more pieces of data The suffix tells whether the data is inside the limits or not segment 2 Data segment nn SCMOD zzPASS or FAIL Self check mode zz passed or failed NUMPS ss NUMFL TS ENDST O
147. k to A6 Receiver cannot talk to AT Receiver cannot talk to A9 handshake error Receiver cannot talk to input buffer A9 U502 Receiver cannot read output buffer A9 U402 Receiver cannot read output buffer A9 U302 nalog hardware error HP h9h5A Operating Verification interface Error Codes Port 1 800 801 802 803 80h 805 806 807 808 820 821 822 823 824 Port 2 900 901 902 903 90h 905 006 007 908 920 921 922 923 92h RS 232 I O processor internal RAM read write error RS 232 ROM checksum error RS 232 External RAM error U202 RS 232 UART internal loopback error HP IL I O processor internal RAM read write error HP IL ROM checksum error HP IL system cannot read write to HP IL chip HP IB I O processor internal RAM read write error HP IB ROM Checksum error Invalid code read from interface Status bit fails to go true after 55 hex written 55 hex code written to I O AA hex code not read back Status bit fails to go true after AA hex written AA hex written to I O 55 hex not written back RS 232 1 O processor internal RAM read write error RS 232 ROM checksum error RS 232 External RAM error U202 RS 232 UART internal loopback error HP IL I O processor internal RAM read write error HP IL ROM checksum error HP IL system cannot read write to HP IL chip HP IB I O processor internal RAM read write error HP IB ROM checksum error Invalid code read from interface Status bit fails to go true after 55
148. l send Data Terminal true When the modem is ready it sets Data Set Ready true These two leads show the status of the hardware Once the hardware is ready the module sets the Request To Send true When the modem responds with Clear To Send true data transfer can begin Data Terminal Ready ERE ILES Data Set Ready Poo ws Request To Send EC OEC Clear To Send EXER Cita Received Line Signal Detected XXXXXX don t care XXX Transmitted data KW valid Received data BARES valid HALF DUPLEX No Handshake This handshake uses only Transmitted Data Received Data and Signal Ground Both the I O module and the external device are ready to receive data at all times The normal command string length must never exceed the buffer size Data Terminal Ready and Request to Send will be asserted Data Set Ready Clear To Send and Received Line Signal Detected will be ignored Data Terminal Ready Data Set Ready XXXXXXKXX don t care XXXX Request To Send Clear To Send XXXEXXXXX don t care XXXX Received Line Signal Detected XXXXXXKX don t care XXXX Transmitted data 3X 44 Xx X4 X AXXxxxxHxAx valid Received data OEC IS UN ea Oe ty valid 7 4 HP 49454A RS 232C Operation Full Handshake This handshake uses Transmitted Data Received Data Signal Ground Lines Data Ter minal Ready Data Set Ready Request To Send Clear To Send and Received Line sig nal Detect When the module is ready to operate it will send Data Terminal true T
149. last command was the parallel poll configure disables the parallel poll response Disables the parallel poll response Unconfigure Returns service request status if enabled otherwise the parallel poll byte is unmodified If it equals the modules address then it becomes listener active If remote enabled goes to Remote state 6 7 HP 4945A HP IL Operation Table 6 1 HP IL Loop Messages and Module Responses con t Unlisten Command UNL Talk Address TAD Untalk Command UNT GET group execute trigger Enable Asynchronous Request EAR Loop Power Down LPO Response Unaddresses module if listener active If equal to modules address then it becomes talker active otherwise it is unaddressed if active talker The module is unaddressed if active talker This command is ignored This command will cause the modules on reception of data from the HP 49L5A to source an asynchronous IDY frame This mode is disabled if any other command is received ihis command is ignored 6 8 HP 49454A HP IL Operation SERIAL POLL OPERATION All messages sent over the serial poll mechanism are system status messages These are characterized by bit 7 which is set This is a group of general purpose mes sages that has been devised to allow simple controllers to better manage the loop regardless of device type and function Bit six is reserved to show whether or not the device requested service it being set if
150. lay measurement and updates the screen Slave The Master sends an FSK signal telling the Slave the carrier frequency it should use Next it sends the envelope delay signal using a fixed frequency carrier 1804 Hz a The Master performs a level frequency and delay measure ment on the incoming signal and displays the results Note Return Reference The Slave performs level and frequency measurement and sends the information to the Master Next it shifts the received modulation to a fixed frequency carrier 1804 Hz and sends it back to the Master to Master Forward Reference N The Slave shifts the received modulation to the carrier frequency requested by the Master This signal is sent to the Master An FSK signal will be sent from the Master unit to the change the frequency Slave unit everytime you 3 64 HP 4945A Operation HOW TO CONFIGURE THE INSTRUMENT FOR MASTER SLAVE OPERATION Let s look at how you put the instrument in Master Slave mode First press the SET UP hardkey to enter the Set Up menu Notice that softkeys 6 and 7 control Master Slave operation Softkey 6 which is labelled MASTR SLAVE cycles between OFF normal operation MASTER and SLAVE Se lect the operating mode for your instrument If you select MASTER the initial linking process will begin Note lo act as the slave in Master Slave the unit does not need to be set to SLAVE This will automatically
151. le the upper sideband encounters more The net result of these phase shifts is that the modulation envelope is shifted in phase or delayed wher traversing a transmission medium The amount of envelope delay is related to the difference in phase between the two sidebands If the phase versus frequency characteristic of the transmission medium is linear then any carrier frequency used with a fixed modulation frequency will produce a constant envelope delay value Plots a and b in Figure 4 18 illus trates this relationship However if the phase versus frequency characteristic is nonlinear then the different carrier frequencies will produce different values Plots c and d in Figure 4 18 illustrate this relationship When different values of envelope delay occur the difference between delay values at two different car rier frequencies is termed envelope delay distortion Envelope Delay Distortion Measurement To make this measurement two TIMS are used in the configuration shown in Figure h 19 The TIMS normal test set transmits a test signal over the voice channel under test to the TIMS repeat test set The repeat set responds by transmitting envelope delay information back to the normal set over the return reference voice channel The normal set compares its received signal with its transmitted signal to determine envelope delay distortion values The normal set transmits an amplitude modulated test signal consisting of a various
152. level is outside the range of the HP h9h3A or HP h9hlA then the two instruments will not be able to establish link up DIRECTION OF TEST MASTER TO SLAVE You are limited to the range limitations of the HP 4943A or HP LOLA since it is performing the measurement receive end The receiver s Slave frequency field will always be blank The HP 945A will only display counts in the impulse noise low area since the HP H0 3A or HP hO9hhA only has one threshold setting which must be set manually When doing the envelope delay measurement you do not have the capability of per forming a LEVEL ZERO This calculation must be done manually If you enter amp menu with a parameter set to an illegal choice then the slave will go into loopback mode Always set up all parameters before entering into Master Slave mode 3267 HP h945A Operation DIRECTION OF TEST SLAVE TO MASTER In this configuration you have additional capabilities You are limited to the receivers capabilities Therefore you are able to do the following Amplitude jitter All 3 jitter bandwidths Noise to ground measurement 3 level impulse noise Phase hits gain hits and dropouts measurements MASTER SLAVE ERROR MESSAGES Why Do They Occur What could cause the Master Slave errors to occur There may be an operational problem with your test set In this case you should run through the self diagnostic capabilities of each unit which is being used Also it is
153. lowpass Voiceband limit MESSAGE CIRCUIT NOISE MEASUREMENT Transmitter quiet termination Receiver Weighting Filters C message 3 kHz flat 15 kHz flat 50 kbit or Program Range 10 to 90 dBrn Resolution i dB Accuracy 1 dB Detector True rms HP h9h5A General Information Table 1 1 Specifications cont NOISE WITH TONE MEASUREMENT Transmitter Frequency 1004 Hz fixed Receiver Weighting Filters C message 3 kHz flat 15 kHz flat 50 kbit or Program Notch Filter gt 60 dB rejection from 995 to 1025 Hz Range 10 to 90 dBrn Resolution 1 dB Detector True rms Accuracy 1 dB SIGNAL TO NOISE RATIO MEASUREMENT Transmitter Frequency 1004 Hz fixed Receiver Weighting Filters C message 3kHz flat 15 kHz flat 50 kbit or Program Notch Filter gt 60 dB rejection from 995 to 1025 Hz Ratio Range 10 dB to 45 dB l Resolution 1 dB Signal level range 40 to 13 dBm at 600 900 and 1200 ohms 34 to 13 dBm at 135 ohms Detector full wave average and true rms Accuracy or 1 dB 10 dB to 40 dB or 2 dB hi dB to 45 dB 1 8 HP h9h5A General Information Table 1 1 Specifications cont NOISE TO GROUND MEASUREMENT Transmitter Receiver Weighting Filters Range Resolution Accuracy Detector quiet termination C message 3 kHz flat 15 kHz flat 50 kbit or Program 40 to 130 dBrn C Message 3 kHz 50 to 130 dBrn Program 15 kHz 50 kbit i dB
154. ment The HP 4945A may be stored or shipped in environments within the following limits o o o o Temp ra amp tur 22 49 3 OSs 40 to 75 C 40 to 167 F Humidity ran ash are oom a 10 to 90 noncondensing Altitude Ay en 4600 m 15 000 ft The instrument should also be protected from temperature extremes which cause con densation within the instrument Original Packaging Use original packaging if available Containers and material identical to those used in the factory are available through Hewlett Packard offices If the instru ment is being returned to Hewlett Packard for servicing attach a tag indicating the type of service required return address model number and full serial number Also mark the container FRAGILE to ensure careful handling In any correspondence refer to the instrument by model number and full serial number HP h9h5A Installation Other Packaging The following general instructions should be used for repackaging with commercially available materials A 2 Wrap the instrument in heavy paper or plastic Use a strong shipping container A double walled carton made of 350 pound test material is adequate Use a layer of shock absorbing material 70 to 100 mm 3 to h inch thick around all sides of the instrument to provide firm cushioning and prevent movement inside container Seal shipping container securely Mark shipping container FRAGILE to ensure careful handling in any correspon
155. minating calls cause relays and switches to operate and release giving rise to impulse noise from the associated electrical transients Normal installation and repair activies also introduce impluse noise Impulse noise affects data transmission by causing the loss of the information sig nal which results in errors In slow data rate systems few errors occur due to im pluse noise because the receiving device can distinguish a data pluse from an im pluse noise pluse As the data rate of a system increases it becomes more difficult for the receiving device to distinguish the data pulse from the noise resulting in impluse noise caused errors Phase Hits Gain Hits and Dropouts A phase hit is amp sudden change increase or decrease in the received signal phase or frequency Phase hits may be as small as tenths of a degree or as large as 360 degrees The phase of the received signal may return to its original value in a short time or it may remain indefinitely at a changed value Waveform c in figure 4 11 illustrates a received holding tone that includes interfering phase hits Some of the more common causes of phase hits and also gain hits and dropouts are automatic switching to standby facilities or carrier supplies patching out working facilities to perform maintenance and noise transients coupled into carrier frequency sources Two common modulation techniques used by data modems are phase and frequency modulation Phase hits cr
156. mmand decoding is aborted if in progress Normal Mode on the HP LOLA is retained 2 13 HP UGh5A HP IB Operation SERIAL POLL OPERATION In the normal mode of operation the serial poll register has the following configuration BIT 7 6 5 4 3 2 1 0 PON RQS ERR READY ddc ddc ddc ddc Bit 7 PON Power on self check failed Bit 6 RQS This device requested service Bit 5 ERR Error occurred Bit 4 READY Data ready for output Bit 3 ddc Device dependent code Bit 2 ddc Device dependent code Bat 1 ddc Device dependent code Bit 9 ddc Device dependent code Bit zero is set in conjunction with ERR when there has been a keycode or mnemonic error Bit 1 is set in conjunction with ERR when the module has been locked out by another module Bit 2 is set in conjunction with ERR when the front panel has been accessed in remote mode It tells the controller that the instrument is now in lo cal state and the set up of the instrument is now unknown to the controller When the status is updated the contents of the serial poll register are ORed with the new status message so many combinations of status message are possible Bit 3 is set when initial link is in progress or when the instrument is in slave mode Io clear the serial poll register it is ncessary to send one of the clear commands DCL or SDC to reset the status bits The one exception to this is the case of data available when the data available bit is reset when the controller has read i
157. n AREA 4 MESSAGES POWER ON SELF CHECK PASSED This means that the instrument has successfully com pleted the power on self check with no errors This message will disappear after the first key press POWER ON SELF CHECK FAILED If the instrument fails power on self check the entire display is blanked and the above message will appear with a list of the failures You may be able to continue using the instrument by pressing any key RECEIVER NOT CALIBRATED This warning message indicates that the receiver is not calibrated The instrument will still operate using default values This can be corrected by running the calibration routine with no errors in the diagnostic self check menu HP 49454A Operation LAST SET UP NOT RETAINED This indicates that there is a problem with the HP HO45A s nonvolatile memory The instrument will still operate but the set up parameters have been reset to default values If the problem continues refer to Section 8 of the Service Manual DATA ENTRY Whenever making a data entry this message will appear in inverse video This indicates that both the data entry keypad and the up down arrow keys are active FREQ CHANGE NOT ALLOWED HERE In certain measurements the definition of the mea surement defines the frequency or frequencies used e g P AR In these cases the above warning message will be displayed with a warning beep if you attempt to change the frequency RANGE XX TO XX XX OUT OF RANG
158. n all the data currently available The service request is also de asserted if there are no errors 5 14 HP 4945A HP IB Operation When a device fails an incorrect mnemonic or an incorrect keycode is detected a SERVICE REQUEST message replaces the REMOTE or the REMOTE WITH LOCKOUT message across the top of the display This message is not displayed for any other service request condition although the SRQ line may be asserted on the bus to tell the controller that the device state has changed Decimal Binary Meaning 16 00010000 Data available in no request mode 80 01010000 Data available with service request 97 01100001 incorrect mnemonic or invalid keycode 98 01100010 Module locked out by other module 100 01100100 Front panel accessed in remote state 22h 11100000 Device failure 2515 HP h9h5A HP IB Operation CONTROLLING THE HP 4945A Commands can be sent from the controller to the HP 4O45A to control the HP 4OL5A setup Following is an example command line OUTPUT select code command data or LF The command is a three character code that is translated into key sequences by the HP 49h5A Data is not required on all commands Output mode is used when printed output is desired and a controller is not avail able The mode is entered and exited from the HP 4945A front panel HP IB commands have no affect when in this mode When the HP 4S45A is in the printed page mode a copy of the display is printed when the
159. n the channel under test will have positive values of power line related noise INTERMODULATION DISTORTION MEASUREMENT The intermodulation distortion mode allows measurement of the second and third order intermoduiation distortion products of two test tone pairs transmitted over a voice channel The test tone pairs are selected to closely approximate the nonlinear distortion properties encountered by data signals to minimize the effects of chan nel roll off phase jitter frequency translation and to avoid inaccurate readings on PCM carrier systems Figure h 20 illustrated the spectrum of the transmitted intermodulation distortion test signal Intermodulation distortion is the generation of new signal components not present in the original transmitted signal This usually happens when a channel s loss in nonlinear with respect to input level The main cause of nonlinear distortion are electronic devices such as modulators demodulators compandors and amplifiers h 26 HP 4945A Measurement Principles With a single frequency fl applied to the input of a nonlinear device the non linear distortion appears as harmonics of the input frequency such as 2f1 381 ufl etc This type of distortion is termed harmonic distortion With a multiple frequency signal fl and F2 applied to the device input the nonlinear distortion appears as harmonics of the individual input frequencies plus intermodulation or mixing products of the input fr
160. ng message Highest priority End of set all neither amplitude or phase EEK DBM Xx HZ AR Q STLVL DBM WARNG ENDST XX 0 RETURN LOSS STL Sine wave SINRL STLVL Ex DB DBM STFRQ dex XX HZ WARNG ENDST Echo CHORL STLVL WARNG ENDST XX 0 HHH TE DBM Status field level Status field frequency Warning message Highest priority End of set P AR reading Status field level Warning message Highest priority End of set Sine wave return loss Status field level Status field frequency Warning message Highest priority End of set Echo return loss Status field level Warning message Highest priority End of set 8 21 HP 4945A I O Module Codes RETURN LOSS STL con t Low singing SRLLO STLVL FAN WARNG XX ENDST O High singing SRLHI SILVESTER WARNG XX ENDST O Measure all CHORL SRLLO SRLHI STLVL we WARNG XX ENDST 0 RETURN LOSS Sine wave ok DB DBM DB DBM 16 TLP SINRL DB TLPLV DBMO STERQ Fran 7 WARNG XX ENDST O Echo CHORL TLPLV Rem WARNG XX ENDST O Low singing SRLLO TLPLV TER WARNG XX ENDST O b DB DBMO DB DBMO Low singing return loss Status field level Warning message Highest priority End of set High singing return loss Status field level Warning message Highest prior
161. nly General Instructions Transmitter 1 2 Press the TEST SELECT hardkey Press the TRANSIENTS softkey 3 The transmitter is now transmitting a 1004 Hz holding tone Adjust the output level to the Data Level using the LEVEL hardkey Note All transmission measurements should be made at Data Level The Data Level for all presently specified data circuits is a power of 13 dB below the Transmission Level Point TLP For example if the TLP is 16 dBm the Data Level would be 29 dBm Therefore an output level of 29 dBm would be applied in this cese General Instructions Receiver i3 2 Press the TEST SELECT hardkey Press the TRANSIENTS softkey 3 Press the COUNT RATE softkey 2 until the desired rate appears in parentheses It cycles through 7 8 and 100 counts per second 3 32 10 11 12 L3 HP h9h5A Operation Press the COUNT TIME softkey 3 and set the timer for the desired limit using the DATA ENTRY keys or the up down arrow keys The allowable range is from 0 to 9999 minutes with 0 being nonstop The up down arrow keys will step in 5 minute steps Press IMP THLD LO softkey h Enter the desired low threshold for impulse noise using the DATA ENTRY keys or the up down arrow keys 1 dBrn step Press the IMP THLD STEP softkey 5 until the desired step size between the impulse noise thresholds appears Your choices are 2 3 4 5 and 6 dB Press the PHASE HITS THLD s
162. of Contents TABLE OF CONTENTS con t Chapter Page Hl IV OPERATION con t Master Slave 3 aos dbi s arra sd a Ve Ue ae De Aenea TI PE DPI General Information gece wd ne creck Mer UA IS ee tas Skee 3 62 How to Configure the Instrument for Master Slave Operation 3 65 Master Slave When Using an HP 4943A or an HP HOLLA with the HEUER N ere re ee aha aoe Ware P ibe won 366 Master Slave Error Messages sees CRUCEM NR AME 3 68 DIMF Signaling Capabilities hac pu ed ad ached Saree oe Oy ANT ek es 3 74 MEASUREMENT PRINCIPLES Tntroduction aae e ae ae HU EN ae en ER del Input tput Su ten nd a ee ee na ee aedi h 1 Date bevelosszi y edad eS awe oe v pp Em PEU OD en h 3 Level and Frequency Measurement TRU Nes ae Mal eM ie E 4 3 TOOG HZ LOE a eo EATEN esce d Fe atria e RUINA ee 4 4 Prequency HT E io sarete aieea a a week ae etd al h h Gain Slope PEE TUER recu ncs ira a E d Sele dig cake dota pali Noise MaeasuremeMbss Jelo 99 bes A a x Else Dx qo quis exer sb Noise Vaud viai V Bard dese ue d Roo wane ioa aue cu acque scura ed matu ME Noise With Tone TEE VPE EA ou EX AD de h 10 Signal to Noise lt teunnes jade p e ire ic avi cin doe EAM ios 4 10 Noise to Ground Measurement 2 22 22 ccc cee eee cereri mare 4 11 Transients Hessurements anfrage d a a er 06 4 12 Impulse Noise ns isn EEE ee ere eee S 4 12 Phase Hits Gain Hits and DUODOULS 01 ak
163. oftkey 6 until the desired phase hit threshold is obtained This key cycles in 5 degree steps from 5 to 45 degrees Press the GAIN HITS THLD softkey 7 until the desired gain hits threshold is obtained This key cycles in 1 dB steps from 2 to 10 dB Ihe current filter which is selected for the noise measurements is displayed on the lower portion of the screen If you want to change to another filter press the SELECT FILTER softkey and select the desired weighting or press the RETURN TO TRANSIENTS softkey 8 Press the VOLUME hardkey Press the VOLUME softkey 1 until ON appears in parentheses Press the MONITOR softkey 2 until RECEIVE appears in parentheses Using the DATA ENTRY keys or the up down arrow keys change the volume to the desired level Listen for any predominant noise which can provide a clue as to the noise source If you decide not to change the volume level press the VOLUME hardkey again to return to the measurement menu Start the measurement by pressing the START STOP softkey 1 until RUNNING ap pears in parentheses The current status of the counters can be observed on the screen When the timer is done STOPPED will appear in the parentheses under softkey 1 Any softkey change will restart the measurement Note The noise with tone reading will be latched while the transients measurement is running 3733 HP 4O4U5A Operation ENVELOPE DELAY DISTORTION Description Ine HP 4GUSA perfo
164. oils Receiver BRIDGED or TERMINATED Setting The VOLUME Control Impulse Noise Thresholds Transmitter Level 99 6 Note If the HP 49454A transmit level is outside the range of the HP 4943A or HP 494LA then the two instruments will not be able to establish a link up HP h9h5A Operation During the initial link up error codes may appear momentarily First the error code H 01 will appear which signifies that no response was received from the Slave This occurs because the HP 4Q45A must take time to verify that it is configured as another HP h9h3A or HP OLUA depending on which unit you are using for the Master This code will disappear if everything is functioning correctly and an other error code may appear momentarily if you are set up in MASTER TO SLAVE direction of test This may be either an H 09 or an H 10 This occurs because the HP 4945A will not send back test results until it has valid data These error codes should all disap pear and the Master Slave operation should be no different than it would be with an HP 4943A or an HP h9hhA acting as the Slave Configuration Considerations When Master is an HP 4945A and Slave is an HP 4943A or an HP 4944A The following items must be set on the HP 4943A or HP h9hhA slave unit before it is in Master Siave mode Transmitter receiver impedance setting Hold coils Receiver BRIDGED or TERMINATED setting Impulse noise threshold Transmitter level Note If the HP 4O45A transmit
165. oise Level change not related to signal Less than 4ms Phase hit Phase change to the signal Greater than 4ms Gain hit Level change to the signal Greater than 4ms Dropout Decrease in signal level of 12 dB Greater than 4ms EVENT CANDIDATES LOW IMPULSE NOISE DETECTOR NOISE WEIGHTING MID IMPULSE NOISE FILTER DETECTOR HIGH IMPULSE NOISE DETECTOR 1000 Kz HOLDING TONE and NOISE TOTALIZER DISPLAY PHASE HIT BAND PASS FILTER Figure 4 12 Impulse Noise Hits and Dropouts 4 16 HP h9h5A Measurement Principles JITTER MEASUREMENTS Phase Jitter The phase jitter mode allows measurement of the peak to peak phase deviation of a 1004 Hz holding tone on a voice channel Phase jitter is unwanted phase or frequency modulation that a signal may pick up as it traverses a communication channel Phase jitter has an insignificant effect on voice transmission however phase jitter can seriously affect data transmission Phase jitter is especially interfering to data communications systems that use phase modulation as the transmission scheme If large phase variations occur one data pulse can occupy the allotted time slot of another pulse intersymbol interference causing an error to occur Figure 4 13a illustrates the effect of phase jitter on a reference holdling tone Different sources cause the instantanous phase of a signal to jitter at rates nor mally less than 300 Hz Phase jitter is typically caused by ripple in the d
166. ok eas lbs ten 4 12 Simultaneous Measurement of Impluse Noise Hits and Dropouts h 15 Jitter Measurements She hee ids Te gates ene ee ene PER WET Phase Jitter EEE yo a ne wi Satake bodes Bar EEE et tel 4 17 Anpiit de Jitters iari ceee rear PER EEE BREITE pee oly Envelope Delay Measurement EON ad Mee See md due EFL NUS 4 21 Relating Phase Shift to Envelope Delay 0 50800 ae cr s 4 21 Envelope Delay Distortion Measurement wae aie kip aS SLE Urs EE Intermodulation Distortion Measurement ccc cece ht 4 26 Peak to Average Ratio Measurement bi ido Oe ee ae 4 28 Return Loss sued era FE EU iue Eri RR Er dar Os ae Eee a er 4 31 iv HP h9h5A Table of Contents TABLE OF CONTENTS con t Chapter Page V HP IB OPERATION INLLOduet Ion i439 093 9 c2 Be ued bla Se stud dad Pert uer eA dengue ates Bed Normal MOS oes ical es d pud eo ated idu aS Wk ae ec artes ed den end e dtd 5 1 Talk Only MONS va a a a ee eir is 5 1 RP OHOJUA MOSES s coperti a ING Nie lhe ebur A t tp bea a 5 1 SPERITILCHLIONE 9x4 du e X a ade ACRI d cede a A epa dius 5 1 PHS Aee al HL M 5 2 PESCE Ve LON we aM um Eu eo Ee dede qmd ns Cad a Geto nico ices a ses 5 3 Communion 20n Cape bi 309 14 45 5 acne che EA X ka duct e DE ede ee UA cbe Ren 5 5 Data input and Output Modes ssc as tind v ua riestus ek IA REEL 5 5 Using the HP h9l5A as an HP h9hhA or an HP h9h3A sess 5 6 HPSIS AddpBESIHB N ARCH MR REO
167. on A18 requires seperate testing Following is a summary of the Mode 14 tests All tests use a 1000 Hz transmit frequency Results Data Displayed Test Segment Should Be signal at A17TP2 Path 1 0 0 1 0 dB 0 0 dBm 600 O Atten 1 2 0 0 1 0 dB 20 dBm 600 20dB Amp 2 3 20 0 1 0 dB 0 0 dBm 600 20 Atten 3 T 15 7 1 0 dB 0 0 dBm 600 135 Ohm 4 5 11 3 1 0 dB 0 0 dBm 600 600 Ohm 5 6 10 7 1 0 dB 0 0 dBm 600 900 Ohm 6 7 10 4 1 0 dB 0 0 dBm 600 1200 Ohm 7 8 0 2 1 0 dB 0 0 dBm 600 Bridge 8 9 12 h 1 0 dB 0 0 dBm 600 900 Ref 9 10 thru 16 not used HP h9l5A Operating Verification Diagnostics Mode 15 MODE 15 IMD Hardware Check A2 A3 A4 A5 A17 A18 This mode tests the A3 circuits The signal is routed from A17 through A2 with no and through A3 where the signal can be picked off from the mixer The Ah wideband autorange is used and A2 filters in input or after the 520 Hz bandpass filter the signal is detected with the AS FWA wideband detector Frequency is measured on A8 Following is amp summary of the Mode 15 tests aB B dB daB dB dB AB aB dB Z dB 2 Results Data Displayed Segment Should Be i 15 0 90 2 15 0 90 3 30 0 90 30 0 90 5 5 0 220 6 5 4 2 0 T 4 9 2 0 8 5 4 2 0 9 1 7 4 2 0 10 520 5 H 41 3 1 2 0 lc 520 4 5 H 13 see Note 1h see Note 15 16 not used Note
168. on im IMP pedance The selections it cycles through are 135 600 900 and 1200 ohms Select the impedance that matches the line to which the slave s transmitter is connected S745 HP h9h5A Operation SLAVE RCVR T This softkey sets the slave unit s receiver IMP termination im IMP pedance The selections it cycles through are 135 600 900 and 1200 ohms Select the impedance that matches the line to which the slave s receiver is connected SLAVE TERM 8 This softkey selects whether the receiver on the slave unit is BRDG BRIDGEd or TERMinated If the slave s receiver is bridged it presents a high impedance to the line This ensures that the test set will not disturb the circuit which is under test If desired the slave can be configured at the slave box Upon initial link the master will display the slave s set up configuration It will not change unless one of the softkeys 6 8 are pressed You should be aware that the following actions will cause you to lose link e Running the diagnostic self check routine e Running the calibration routine e Reversing the transmit and receive lines using the hardkeys located above the terminals In order to recover you must go through the initial link up process again 3 16 HP 49454 Operation The HP 4945A will supply the handset with 15 Vde to energize the microphone Not Used Not Used Not Used Not Used 3 19 HP h9h5A Operation Refer to Table 3 1 for t
169. ops the sweep It toggles between STOPPED and SWEEPING This softkey toggles between SINGLE and NONSTOP NONSTOP allows you to con tinuously sweep Enter the frequency you want the sweep to start from Enter the frequency you want the sweep to end on Enter the step size you want between the frequencies Select how fast you want the sweep to step This key cycles through slow 3 steps second medium 1 step second and fast 3 steps second Not Used This softkey will return you to the level frequency menu General instructions Transmitter Press the TEST SELECT hardkey Press the LEVEL FREQUENCY softkey 1 The Level Frequency menu will appear Note The transmitter is automatically set to 1004 Hz when entering the Level Frequency menu Adjust the level to the Data Level Note All transmission measurements should be made at Data Level The Data Level for all presently specified data circuits is a power of 13 dB below the Transmission Level Point TLP For example if the TLP is 16 dB the Data Level would be 29 dBm Therefore an output level of 29 dBm would be applied in this case When requested by the receiver operator transmit the agreed upon test frequen cies The frequency can be changed by entering amp specific frequency using the up down arrow keys both of these methods are explained in Data Entry Procedure Section or by using the programmable sweep capability shown on softkey 8 above refer
170. over a specified time The nominal count rate for electromechanical counters is 7 counts per second with a blanking interval of 143 milliseconds The nominal fast counting rate is 100 counts per second with a blanking interval of 10 milliseconds All of the transients can oc cur at any time because they are caused by random sources They can also occur in clusters with only a few milliseconds between each impulse noise spike Because not all disturbances are of sufficient magnitude to cause data communication problems it is necessary to be able to set thresholds that will discriminate against small disturbances The thresholds in the HP HOLSA are adjustable so that measurements can be made at different test level points and also so that the test set can be made to be susceptible to certain disturbances depending on the effect those disturbances have on current data communications This test set is capable of identifying all four disturbances simultaneously Each is counted individually as shown in Figure 4 12 4 15 HP h9h5A Measurement Principles Table 4 2 Transient Phenomena Summary DISTURBANCE SIGNAL RELATED CHARACTERISTIC DURATION No Impulse noise lt Q Ims to 4ms Level and Phase Phase hit Yes Phase lt 0 ims to gt hours Gain hit Yes Level 0 1ms to gt hours Dropout Yes Level wAims to hours Table 4 3 Measurement Definitions DISTURBANCE SIGNAL RELATION DURATION Impulse n
171. pe delay Therefore the envelope delay value received at the normal set will represent the envelope delay value received at the repeat set plus the constant envelope delay of the return reference channel The receiver of the normal set amplitude demodulates the incoming return reference Signal The phase of the incoming return reference envelope is then compared to the original 83 1 3 Hz oscillator signal to determine the difference in phase envelope delay between the two signals To measure the change in envelope delay from the normal set to the repeat set with a change in carrier frequency a delay zero control is used to zero out the envelope delay of the entire measurement loop The delay zero control sets the phase difference or envelope delay between the 83 1 3 Hz oscillator and the demodulated return reference envelope to zero was set By changing the normal set carrier frequency from the delay zero reference value the only changing envelope delay envelope delay distortiion occuring in the measurement loop is that incurred by the test signal traversing the voice channel under test The delay zero function is usually implemented at a normal set carrier frequency of around 1800 Hz For some tests it is convenient to set an arbitrary zero and vary the test frequency while looking for the largest negative envelope delay value By setting a new zero value at this frequency of minimum delay all other envelope de lay measurements o
172. peat Test Set Ta 2 Press the TEST SELECT hardkey Press the ENVELOPE DELAY softkey 4 The envelope delay menu will be displayed a Press the NORMAL REPT softkey 1 until REPEAT appears in parentheses Connect the pair to be tested to the RCV terminals Connect the return reference pair to the TRMT terminals Adjust the output level to the Data Level using the LEVEL hardkey 3 38 fa HP 49454A Operation Note All transmission measurements should be made at data level The Data Level for data circuits is a power of 13 dB below the Transmission Level Point TLP For exam ple if the TLP is 16 dB the Data Level would be 29 dBm Therefore an output level of 29 dBm would be ap plied in this case Adjust the transmit frequency to the reference frequency e g 1804 Hz or the frequency of minimum delay using the FREQuency hardkey Note The transmitter of the HP 4OolSA is automatically set to 1804 Hz when the envelope delay menu is accessed Notify the Normal Test Set operator that you have completed Step 6 General Instructions Forward Reference Normal Test Set 14 2 6 Press the TEST SELECT hardkey Press the ENVELOPE DELAY softkey 4 The envelope delay menu will be displayed Press the NORMAL REPT softkey until NORMAL appears in parentheses Connect the pair to be tested to the RCV terminals Connect the reference pair to the TRMT terminals Adjust the output level to the
173. pulse threshold spread 6 dB Phase hit threshold 5 deg Phase hit threshold 10 deg Phase hit threshold 15 deg Phase hit threshold 20 deg Phase hit threshold 25 deg Phase hit threshold 30 deg Phase hit threshold 35 deg Phase hit threshold LO deg Phase hit threshold 45 deg Gain hit threshold 2 dB Gain hit threshold 3 dB Gain hit threshold h dB Gain hit threshold 5 dB Gain hit threshold 6 dB Gain hit threshold 7 dB Gain hit threshold 8 dB Gain hit threshold 9 dB Gain hit threshold 10 dB Duration of test Low impulse threshold Normal mo Output mo HP IB address entry de de RS 232 ENQ ACK protocol RS 232 TX on off protocol RS 232 No software prototcol RS 232 Auto handshake RS 232 No handshake 8 1 T HP 49X454 I O Module Codes no no no no no no no no no no no no no no no no no no no no no no no no no no yes yes no yes no no no no HP lol5A 1 0 Module Codes Mnemonic Function I O SET UP COMMANDS con t 108 109 IOA IOB IOC IOD TOES IOF IOG IOE 107 IOJ lOK TOL IOM ION I00 TOP 10Q IOR 105 JITTER JTO T dle JT3 JT JT5 JT6 JTT LEVEL FREQUENCY LFO LES LF 2s Set baud rate 50 Set baud rate 75 Set baud rate 110 set baud rate 150 Set baud rate 300 Set baud rate 600 Set baud rate 1200 Set baud rate 2400 Set baud rate 4800
174. r test The termination mode provides a resistive termination on the receive circuit to provide proper loading When a termination is provided by some other device it is not necessary to provide a termination In this case the receiver input should be used in the bridged mode h 1 HP 4OLSA Measurement Principles Zutyoytms yndyno anduy p p aanbry HAILUASNVEL ud XYLAWIU OL 1H9lH l 1 OLE 3M H3illANSNVHA SHOLSISIH LINISH i45 8 2 O1 NOLLVNHAH3L q10H 13534 9 Pur idi 13534 Lt dit ONIY dIL SS01 NUNLAH NOMLIFI3S Hlvd T 1431 1H91H C oT l OLE aM m HNW ONIY L1H5IH H3AI393Y SYOLSISIU G10H Di NOU VNIIAH3L 7 383 9 Q D dii zy 13534 Hi syovr 3Nvd INO 4 2 HP OSA Measurement Principles The HP 4O45A input and output circuits are balanced to match standard telephone voice channel lines A balanced line is one that is electrically symmetrical the two sides of the line have equal series resistance series inductance shunt capacitance and leakage to ground Only test sets or other devices with balanced inputs and outputs will operate properly when connected to a balance line To allow dialing talking and listening over the circuit under test handset ter minals are provided for the connection of a lineman s handset In addition talk battery is selectable for use on dry circuits circuits which do not incorporate a power source to provide direct current flow for the microphone DATA LEVEL
175. rd and includes the phase jitter interference caused by 20 Hz ringing and 60 Hz power plus their first several harmonics Phase jitter components rarely occur above 300 Hz When they do they are normally accompanied by large amounts of jitter below 300 Hz which allows detection by the HP 4ousa In addition to the Bell Standard 20 to 300 Hz band the HP hOl5A also measures phase jitter in the low frequency LF 4 to 20 Hz band and in the Bell Standard plus LF 4 to 300 Hz Amplitude Jitter Amplitude jitter is the summation of incidental amplitude modulation and the effects of interference and noise Amplitude jitter is measured by examining amplitude dis turbances on a 1004 Hz test tone Figure h 13b shows the effects of amplitude jitter on the 1004 Hz 4 17 HP 4O45A Measurement Principles The most commonly round signal frequency components of amplitude jitter are 20 Hz ringing 60 Hz commerical power and their second through fifth harmonics A bandwidth of about 600 Hz centered about a carrier near 1 kHz will recover the major suspected amplitude jitter without incurring large amounts of uncorrelated interference Because group delay distortion of a channel can cause amplitude jitter to be created from phase jitter and vice versa amplitude jitter should be measured in conjunc tion with phase jitter Also noise can cause what would appear to be amplitude jit ter so a C notch weighted noise measurement should always be mad
176. re three ways of changing the level of the instrument They are The DATA ENTRY keys the up down arrow keys or selection of one of the preprogrammed levels The procedure for each of these is discussed below DATA ENTRY Keys When making a specific entry first press the LEVEL hardkey the DATA ENTRY lock will come up on the screen in inverse video with an acceptable entry range on the line above it Next press the appropriate keys on the keypad to make the level entry The entries will show up in the DATA ENTRY block To finalize your selection press the ENTER key Up Down Arrow Keys These are located right below the LEVEL FREQuency and VOLUME hardkeys on the front panel The up down arrow keys can single step up or down a value The amount of the step size is set in this menu by pressing the STEP SIZE softkey 7 The choices available are 1 5 1 dBm Programmable Levels When the LEVEL hardkey is pressed the softkey selections shown in figure 3 5 appear Note The values may be different To change the level press the corresponding softkey The values shown that correspond to softkeys 1 5 can be reprogrammed as follows e Press softkey 8 which is labelled PROGRAM LEVELS Notice that each of the levels is in parentheses e To change any of the values press the corresponding softkeys Now use the data entry keys or the up down arrow keys to change it to the desires value 3 8 HP 4945A Operation Frequency
177. rms the envelope delay distortion measurement which is an indi rect method of measuring the phase response of a channel It has a programmable frequency sweep capability to aid you in characterizing a line The following figure is included to quickly familarize you with the measurement procedure and terms 4945A IN NORMAL MODE MIC ROSEC TX a Return Reference Technique 4945A IN NORMAL MODE microsec X b Forward Reference Technique 49454 IN REPEAT MODE Normal operator varies his transmitted carrier frequency Repeat operator sets up a fixed reference carrier frequency Enveiope Delay Distortion measured at Normal Set 4945A IN REPEAT MODE 83 1 3 Hz Normal operator sets up a fixed reference carrier frequency Repeat operator varies his transmitted carrier frequency Envelope Delay Distortion measured at Normal Set Figure 3 17 The Envelope Delay Test Set Up 3 34 HP 4GLSA Operation To enter the envelope delay menu press the TEST SELECT hardkey and then the ENVE LOPE DELAY softkey 4 The following menu will appear 09 28 83 10 51 AM NDRHRL REPT ENVELOPE DELRY NORHAL ED LEVEL ZERO DELAY 4313 USEC RCV LEVEL 13 0 dBm DELAY ZERO RCY FREQUENCY 1804 Hz I IRCV TERHI 1804 Hz 13 0 dB 1804 Hz 13 0 dBm Figure 3 18 The Envelope Delay Measurement Menu 1 This softkey sets up the instrument as the NORMAL or as the REPEAT test set This key is bl
178. rogram con t 290 300 310 320 330 340 350 360 370 380 390 400 410 420 430 uo 450 460 470 480 490 500 510 520 230 540 550 560 570 580 290 600 610 620 630 640 650 660 670 680 690 BEEP INPUT WHAT IS THE TRANSMIT IMPEDANCE Tr_imp IF NOT Tr imp 135 OR Tr imp 600 OR Tr_imp 900 OR Tr_imp 1200 THEN GO TO 290 E The entered transmit impedance must be 135 600 900 or 1200 ohms Program the HP LOUSA to the proper transmitter impedance i IF Tr imp 135 THEN OUTPUT GTims TRO IF Tr imp 600 THEN OUTPUT Tims TR1 IF Tr imp 900 THEN OUTPUT Tims s TR2 IF Tr imp 1200 THEN OUTPUT Tims TR3 j i Prompt the user for receiver impedance BEEP INPUT WHAT IS THE RECEIVER IMPEDANCE Rec _imp IF NOT Rec_imp 135 OR Rec_imp 600 OR Rec _imp 900 OR Rec imp 1200 THEN GOTO 390 The entered receive u impedance must be 135 600 900 or 1200 ohms Program the h9h5A to the proper receiver impedance IF REC imp 135 THEN OUTPUT Tims TRY IF Rec impz600 THEN OUTPUT Tims TR5 IF Rec imp 900 THEN OUTPUT Tims TR IF Rec imp 1200 THEN OUTPUT Tims TR7 a pee dom pre peer A smm om doe Prompt the user for reference frequency BEEP INPUT WHAT IS THE REFERENCE FREQUENCY Ref fre l Test to see if the frequency is in the range of the HP 495A i IF NOT Ref fre 20 AND Ref fre lt 110004 THEN GOTO 390 IF NOT Tr imp 135 THEN GOTO 590 IF NOT Ref fre 200
179. rough 600 900 ohms and EXT EXT means that you can use an external reference impedance which can be connected to the jacks on the rear panel If you are in h wire mode this softkey is labelled HYBRID LOSS You can enter the transhybrid loss of your network using the DATA ENTRY keys This softkey is displayed with SINE WAVE return loss only softkey 2 It ac cesses the programmable frequency sweep menu 3 51 HP h9l5A Operation When you select SINE WAVE softkey 2 in the Return Loss menu softkey 8 becomes PROGRAM SWEEP When this is pressed the menu shown below is displayed After set ting softkeys 2 through 6 start the sweep by pressing softkey 1 until it reads SWEEPING in parentheses 09 28 83 10 56 RH JUGE C PROGRRH SUEEP STOPPED SINE URVE 0 0 dB ECTSI EM SWEEP SUEEP FROM 300 Hz SUEEP TO MA 3400 Hz STEP SIE SUITE STEP RATE 5 SLOW 7 8 Figure 3 24 Puce Sweep Menu for Heturn Loss l This softkey starts and stops the sweep It toggles between STOPPED and SWEEPING 2 This softkey toggles between SINGLE and NONSTOP NONSTOP allows you to con tinuously sweep 3 Enter the frequency that you want the sweep to start from 4 Enter the frequency you want the sweep to end on 5 Enter the step size you want between the frequencies 6 Select how fast you want the sweep to step The key cycles through slow 3 steps second medium 1 step second and fast 3 steps second
180. rying case Restriction of air from the fan can cause overheating and damage to the test set 3 Select the terminals that will be used for transmit and receive by using the appropriate hardkey located above the terminals 4 Connect the HP 4945A to the circuit under test 5 To initially configure the instrument press the SET UP hardkey The following menu will appear Note The HP 49454 contains nonvolatile memory which saves your set up information after power down It does not retain your hold coil settings or measurement results If you are in master slave mode when you power down you will return to normal operation upon power up 3 2 HP h9h5A Operation 10 41 AN i 38 CRLIBRRTE SELF CHECK TRAT ARCVR SET UP TRHT IMPEDANCE 600 EEE RCYR IMPEDANCE 600 DIAL HOLD RCYR TERH BRDG SET UP SF SKIP OFF VOICE BAND LIHIT FF 170 PORT TRHT HOLD COIL __SET UP RCVR HOLD COIL mimi DATE TINE SET UP MASTR SLAYE COFF C HASTER ES TO SLAVE 13 o dBm 004 Hz 13 0 dBm 004 Hz Figure 3 8 Set Up Menu This softkey accesses the menu to run the calibration and self check routines This softkey accesses the menu to configure the transmitter and receiver This softkey accesses the menu for the dial talk talk battery and holding capabilities This softkey accesses the menu to set up the I O ports This softkey accesses the menu to set the date and and time shown at the top of the display
181. s indicates that the voice band limit function is active RCV or TMT MNTR If the volume is on this indicates whether you are listening to the receiver or the transmitter 3 60 HP 4OU5A Operation MS TO SL or SL TO MS When in Master Slave this indicates the direction of the test that is selected LINKING This message will flash while the instrument is re linking while in master slave mode LOOPBACK This indicates that the slave unit is repeating the received signal at the level selected This only occurs in master slave mode The lower two lines contain the current level in dBm frequency and terminating impedance of both the transmitter and receiver If the handset terminals are ac tive on the front panel then the message HANDSET will be displayed on the transmit ter line 3 61 HP h9h5A Operation MASTER SLAVE GENERAL INFORMATION What is it Master Siave is a method for remotely controlling a distant TIMS using the lines under test Master Slave can only be utilized on h wire circuits This technique virtually eliminates the need for another person at the far end after the instrument is powered up Another direct advantage is that a separate dial up link isn t re quired for communication purposes Also testing time is reduced by eliminating the coordination time needed when running a test using two people Testing can be done on either pair of the four wire circuit The handshaking that takes place betwe
182. s input to Ah and is measured on the A8 wideband channel HP h9l5A Operating Verification Diagnostics Mode 8 MODE 8 Transmitter Multi tone Check A4 A8 A14 A15 This mode connects the A15 self test signal output directly to the Al input multiplexer Four frequencies are sequentially applied to All UhO2 U403 UlOh and UL05 with latch address 2 01 selected The test then repeats using latch addresses three 10 and four 11 These frequencies are read by the A8 frequency counter Any errors in the multi tone system appear as frequency offsets Following is a summary of the Mode 8 tests Results Displayed Should be Data Segment 1 Latch Add 2 15 Hz 15 0 1 2 Latch Add 2 240 Hz 240 Q 2 3 Latch Add 2 3840 Hz 3840 0 3 4 Latch Add 2 61440 Hz 6144 0 4 5 not used 6 Latch Add 3 15 Hz 15 0 5 7 Latch Add 3 240 Hz 240 0 6 8 Latch Add 3 3840 Hz 3840 0 7 9 Latch Add 3 61440 Hz 6144 6 8 10 not used 14 Latch Add 4 15 Hz 15 0 9 12 Latch Add 4 240 Hz 240 0 10 13 Latch Add 4 3840 Hz 3840 0 11 14 Latch Add 4 61440 Hz 6144 0 12 15 16 not used HP 4O45A Operating Verification Diagnostics Mode 9 MODE 9 Transmitter Filter Sweep A4 A15 This mode connects the A15 self test signal output ST16 to the Au input multiplexer Two frequencies are applied to the two A15 lou pass filters and three frequencies are applied to the A15 IMD ban
183. s of background noise and tones Figure 4 3 illustrates the basic setup for these measurements Noise The message circuit noise mode measures the noise present on voice channel which has a quiet termination on one end supplied by transmitting TIMS and a weighted measuring device on the other end received TIMS The quiet termination is a simple resistive termination on the wire pair and the transmitter is off At the measurement end of the voice channel a choice of frequency weighting filters is available The filters that can be selected are C message 3 kHz flat 15 kHz flat 50 Kbit or program see figures 4 4 thru 4 8 The required measurement range for noise is a function of the type of filter selected Table 4 1 list the filter noise range The C message filter allows measurement of only those noise signals that are of annoyance to the typical subscriber of standard telephone service The C message weighting is also used to evaluate the effects of noise on voice grade data circuits The C weighting is valid for data transmission since the response characteristic is relatively flat over most of the frequency range of concern for data transmission 600 to 3000 Hz Table 4 1 Filter Noise Ranges Filter Noise dBrn Noise to Ground dBrn C message 40 to 130 3 kHz Flat 40 to 130 15 kHz Flat C notched noise 50 Kbit 135 ohm impedance 4 5 HP h9h5A Measurement Principles TRANSMITTING TIMS RECEIVING TIMS QUI
184. s that the test signal is being generated transmitted at the Master end and is being received at the Slave end initial Link up In the initial link up the Master requests identification from the Slave The HP LOUSA needs to know if it is interfacing with another HP 4945A or an HP 4943A or HP NOhhA so it can configure itself amp ccordingly Note that Master Slave operation with the last two instruments mentioned is covered at the end of this chapter Next the Slave sends back the type of instrument it is and what its current parameters are These parameters consist of its current level impedances and mea surement information During this process the message LINKING PLEASE WAIT will be displayed on the screen If an error or no response is detected in any of the above transmissions then the process will start over If a link is not established after a reasonable length of time then the message UNABLE TO COMPLETE M S LINK Will be displayed The Master will continue trying to link until it is taken out of Master Slave mode Re link Once linked when an action takes place which affects the Slave a re link takes place The message LINKING will flash on the screen This will happen when enter ing amp measurement changing the Slave s impedances changing the direction of test etc When entering a measurement the Master will request the Slave to enter a specific measurement designate the direction of test and will inclu
185. set to the same values otherwide you will receive erroneous readings If you want to run a frequency sweep between the 2 instruments only set up the sweep function softkey 8 on the transmitting instrument The receiving in strument should be set up for SINE WAVE return loss The receiving instrument will recognize the incoming frequencies and display the return loss reading 329 HP h955A Operation HOW TO DUMP THE DISPLAY TO A PRINTER USING THE OUTPUT HARDKEY Using the OUTPUT hardkey an image of the display can be sent to a printer The only part of the screen that will not be printed are the softkey selections On your printout there will be a line of s and then the display will be printed followed by another line of s While it is printing the word PRINTING will be flashing at the bottom portion of the screen The instrument will still be making measurements even though the screen is frozen while printing When the printing process is finished the screen will automatically update the results on the screen Pressing any key on the front panel will stop the printing action Also because there is not an ASCII equivalent to the up and down arrows which are displayed oc casionally and signs will be printed in their place Notes for each of the different types of printers are contained below When using an HP IL printer If your printer is already connected to the HP IL module on your HP hOh5A skip to step 3 1 With
186. shold settings Applicable only if using an HP h9l3A or an HP 4ouua 3 f3 HP h9h5A Operation Slave Unable To Do Measurement When After link up Pilot Tone Yes Data Yes Direction of Test Either Problem Channel No Additional Comments This error occurs when the Master requests the Slave to per form a measurement which is beyond its capabilities The Slave will not go into loopback mode DTMF SIGNALING CAPABILITIES The HP h9h5A provides Dual Tone Multi Frequency DTMF signaling This feature al lows touch tone dialing The following table lists the segments and their cor responding function Segment Function 1 1 2 2 3 3 T 4 gt 2 6 6 T T 8 8 9 9 10 O 2 ai 12 13 Erases memory 14 Adds pause to dialing 15 Resumes dialing after pause 16 Dials number automatically To access the feature enter the diagnostics self check menu and select SEGMENT self check MODE 99 Then set the segment number to SEGMENT 13 and press the START STOP key SEGMENT 13 clears out any previous number stored in the memory A telephone number of up to 50 digits can be entered in memory Each digit is entered by selecting the SEGMENT for that digit and pressing START STOP After the entire number has been entered select segment 16 and press START STOP The number will then be dialed automatically 3 74 HP h9h5A Operation A controller can be set up in a programming loop to dial the number automatically
187. ss the external reference jacks or a de path using internal reference HP 4945A Operation 6 T Adjust the output level using the LEVEL hardkey Note The HP 4S45A uses the reference impedance selected on softkey 7 to determine the level in dBm If you have selected the external reference impedance option it uses the impedance which was previousiy selected for the transmitter Select the desired test signal by choosing between softkeys 2 through 6 If performing sine wave return loss select the measurement frequency using the FREQuency hardkey Note The HP 4945A automatically begins transmitting a 2150 Hz tone when SINE WAVE return loss is accessed This will disable any echo suppressors on the line Also the HP 49454 has the programmable sweep capability which comes up on softkey 8 after SINE WAVE return loss has been selected This is explained in the previous section The return loss readings will be displayed on the screen General instruction 4 Wire Return Loss m Connect the TRMT and RCV terminals to the hybrid under test Press the TEST SELECT hardkey Press the RETURN LOSS softkey 8 The return loss menu will be displayed The HP h9h5A has two different four wire selections on softkey 1 The selec tions are labelled 4W O TLP and 4W 16 TLP Select the one which matches the transmit TLP at the point you are going to test in the circuit Note When testing at a 16 dBmO TLP point a receive TLP at
188. t bp OXON ONU EE T pcd BASE Tm e Va es ice vu eye Ns visa iind A 6 HP 4O45A List of Illustrations LIST OF ILLUSTRATIONS Figure Page 3 1 Front Panel Controls Connectors and Indicators ven 3 2 3 2 Rear Panel Controls Connectors and Features eee 3 h dew Display Bestures soni cae ERU ove he s cu Ove red OR ae ee 3 5 3 h Data Entry Level Frequency and Volume Hardkeys 3 7 3 5 Level SOLUNGY Sel ofi987Sos s6x2 Que Reip d actes re 3 7 3 6 Frequency Softkey Selections ccecccccucecevcecevevaevaces 3 9 3 7 Volume Softkey Selections stg De ara ee d ib 3 10 3 8 pet Up Mansit e ad doe kr E ea vu Rec V aet Rw We EROS ae 3 13 3 9 Transmitter an Receiver Set Up Menu en 3 14 3 10 Clock Set Up MEN sues puse Tbe Wr E ae adr E VE Vito a e end Re tg BALT 3 11 Dial Hold Set Up SI 3718 3 12 The Level Frequency Measurement Menu cent 3 21 3 13 Programmable Sweep Menu for Level Frequency Measurement 3 22 3 14 The Noise Measurement Menu een 3 26 3 15 The Noise Filters Men ciei s uses EASAN 3 27 3 16 The Transients Measurement Menu cn 3 32 3 17 The Envelope Delay Test Set Up dodi en 3 34 3 18 The Envelope Delay Measurement Menu ee iin 3 35 3 19 The Programmable Sweep Menu for Envelope Delay Distortion 3 36 3 20 The Intermodulation Distortion Measurement Menu nenn 3 42 3 21 The Jitter Meaturehent OU 2 oo P Ge ek ENERNS EEE TE 3 45 vii HP h9l5A
189. t of Range H 10 When After link up Pilot Tone Yes Data No Direction of Test Either Problem Channel Test Channel Additional Comments This error means that the instrument acting as the receiver is unable to perform the measurement because the test Signal is out of range No Carrier Received From Slave H 11 When During link up only Pilot Tone No Data Direction of Test During link up Either Problem Pair Either Additional Comments The master unit in this case is receiving a signal but it is not the correct frequency 1990 Hz ar HP h9h5A Operation Slave Initiated M S Link Abort H 13 When Anytime Pilot Tone Yes Data Yes Direction of Test Either Problem Channel No Additional Comments This message occurs if the slave sends an abort to the master This only happens when the slave is taken out of slave mode at the far end Dropout 1 Sec Test Aborted H 14 When After link up Pilot Tone Yes Data No Direction of Test Either Problem Channel Test Channel Additional Comments This error will only occur when you are in impulse noise and you lose the holding tone 100h Hz The instruments will terminate the test Phase Jitter Overrange H 15 When After Link Up Pilot Tone Yes Data No Direction of Test Either Problem Channel Test Channel Additional Comments This message is
190. t of measured value pius or 0 5 percent of peak Demodulated carrier and jitter available 1004 Hz fixed and quiet termination are selectabie 995 Hz to 1025 Hz 40 dBm to 10 dBm at 600 900 and 1200 ohms 3h dBm to 10 dBm at 135 ohms 7 8 or 100 counts per second 0 to 9999 for all count indicators 1 to 9 999 minutes cc continuous HP h9l5A General Information Table 1 1 Specifications cont e a a a ne T Note The following accuracy specifications apply to the 7 and 8 counts per second rates only Impulse Noise Threshhold Range Threshold Accuracy Phase Hits Threshold Level Reference Threshold Accuracy Gain Hits threshold Range Reference Threshold Accuracy Dropouts Threshold Threshold Accuracy Duration Reference low 30 to 110 dBrn in 1 dB steps medium programmable 2 3 4 5 or 6 dB above low high programmable 2 3 4 5 or 6 dB above medium 1 dB 5 to 45 degrees in 5 degree steps Hit Guard Interval Nominal 4 msec HP 4945A set for Impulse Threshold lt 90 dBrn 0 5 degrees 10 of threshold setting 10 to 45 degrees 2 to 10 dB in 1 dB steps Hit Guard Interval Nominal 4 msec HP 4945A set for Impulse Threshold lt 90 dBrn 0 5 dB gt 12 dB 1 dB Nominal 5 msec HP 4945A set for Impulse Threshold lt 90 dBrn HP h9h5A General Information Table 1 1 Specifications cont ENVELOPE DELAY M
191. the 1380 Hz tone pair and the 860 Hz tone pair The two levels are subtracted and the results are displayed This mode can be used for adjusting the tone pairs to the same relative level IMD Flatness The level can be set to within 0 1 dB of each other When the level difference is 5 dB or greater the difference is displayed in inverse video to indicate a gross failure
192. the Program filter This filter is used for the weighted measurement noise on program circuits which have bandwidths up to 8 kHz 5 This softkey selects the 50 kBIT filter This filter is used on circuits which handle wideband data and DDS circuits 6 Not Used T Not Used 8 This softkey returns you to the measurement menu General Instructions Transmitter 24 2 Press the TEST SELECT hardkey Press the NOISE softkey 2 The Noise menu will be displayed Message Circuit Noise Press the MESSAGE CET NOISE softkey 4 This will quiet terminate the transmitter Signal to Noise Ratio Press the SIGNAL TO NOISE softkey 3 The transmitter is now transmitting a 1004 Hz holding tone Adjust the output level to the Data Level using the LEVEL hardkey 3 28 HP Louisa Operation Note All transmission measurements should be made at Data Level Data Level for all presently specified data cir cuits is a power of 13 dB below the Transmission Level Point TLP For example if the TLP is 16 dB the Data Level would be 29 d Bm Therefore an output level of 29 dBm would be applied in this case Noise to Ground The HP 4945A must be properly grounded for valid noise to ground measurements Ground can be established through the power cord ground if there is a reliable power line bond or through the sleeve connections on the 310 transmit receive jacks 6 Press the NOISE TO GROUND softkey 5 The transmitter is
193. the TEST SELECT hardkey and then the P AR softkey 7 The following menu will appear 100 P RR UNITS 41 Rd EE RCV 16 0 dBm 600 THT P RR TONES 16 0 dBm 600 Figure 3 22 The P AR Measurement Menu T 8 Not Not Not Not Not Not Not Not Used Used Used Used Used Used Used Used There are no softkey selections for this measurement General instructions Transmitter L 5 ce Press the TEST SELECT hardkey Press the P AR softkey 7 The P AR menu will be displayed Adjust the output level to the Data Level using the LEVEL hardkey Note All transmission measurements should be made at Data Level The Data Level for data circuits is a power of 13 dB below the Transmission Level Point TLP For exam ple if the TLP is 16 dB the Data Level would be 29 dBm Therefore an output level of 29 dBm would be ap plied in this case General Instructions Receiver i ds 35 Press the TEST SELECT hardkey Press the P AR softkey The P AR menu will be displayed Observe the P AR UNITS on the display 3 49 HP 4945A Operation HP LOUS5A Operation RETURNLOSS Description The HP h9h5A performs both 2 and h wire return loss In 2 wire return loss you have the capability of using an external reference impedance in addition to the standard 600 and 900 ohm selections In 4 wire return loss there is an adjustment for transhybrid loss You can perform the
194. the output of data and the input of commands These commands are the OUx commands The OUO command is a mask service request when data is available command The data available message will be put in the status register when data is ready and removed when there is none The OUl command will cause the I O module to make a service request when it has data available for the controller Both the service request bit and the data available message bits in the status register are set when data is available and a service request is made The bits are reset when there is no more data The OU2 command causes the module to hold off the HP IL loop handshake after a line feed which terminates a mnemonic command until all mnemonics have been decoded and accepted by the HP 4945A This is the default state of the module Ihe OU3 command causes the module to release the data handshake on the HP IL loop as soon as the codes have been received This mode enables parallel operation of many instruments without waiting for each to accept the codes before programming the next When using this mode it takes one to two seconds for each mnemonic to be decoded and accepted For example in an application where the HP 4945A transmitter is being used and an other TIMS receiver is being used to take the reading the transmitter output may not be the expected value if there is insufficient delay before the reading 6 h The HP 18165A Interface has the following H
195. the slope each is expressed times 1000 The dc offset is in millivolts and the gain constant is in dc volts output divided by the ac volts input displayed in the appropriate measure of ac e g average rms or peak The comparator dc offset is an intentional dc offset in the A to D converter which _measures all detector outputs The offset lets the ADC measure detector offsets that are less than 0 volts Thus the input voltage range of the ADC is 10 volts Wide but is shifted by the negative dc offset voltage of the comparator Note Data segment 1 must be run before any other path since the data acquired in data segment 1 is used by the other data segments Following is a summary of the Mode 2 tests Results Data Displayed segment Test Should Be Path 1 190 mV dc offset ADC comparator 188 18 mV i 2 not used 3 O de offset rms detector O 10 mV 2 4 1000 gain constant rms detector X1000 1000 20 3 5 not used 6 O de offset FWA wideband detector O 170 mV h T 2000 gain constant FWA wideband det X1000 2000 4 20 5 8 0 de offset FW rectified path 0 40 mV 6 9 909 gain constant FW rectified path 909 5 7 10 not used 11 O dc offset FWA narrowband detector O 70 mV 8 12 2000 gain constant FWA narrowband det X1000 2000 20 9 13 O dc offset FW rectified path 0 15 mV 10 14 1909 gain constant FW rectified path X1000 909 5 11 15 not used 16 not used A 9 HP 49454A Operating Verification Diagnostics Mode 3 MOD
196. this replacement send at least one other transient control command after selecting noise filter NORMAL DISPLAYS HARDKEY NMD Normal displays 8 19 no HP 4945A I O Module Codes Mnemonic NOISE COMMANDS NOO NO1 NO2 NO3 Function Data Entry Noise with tone no Signal to noise no Noise no Noise to ground no OUTPUT ERROR RS 232 only OE OUTPUT IDENTIFICATION DI ECHO ON OFF RS 232 only ONE OFE Output the string STSWD ddd CrLf where ddd is a three character ASCII number including leading spaces Output the string HPh9h5A no when talk addressed Echo mode on no Echo mode off no LOCKOUT ON OFF RS 232 only ONL OFL Enter remote with local no lockout mode Enter local mode no OUTPUT COMMANDS HP IB and HP IL only QUOS QU QU2 QU OUTPUT HARDKEY QUT Mask SRQ on data available no Generate SRQ on data ready no Hold off linefeeds until ready no Release linefeeds no Same as output hardkey no 8 20 HP 49454 I O Module Codes Mnemonic Function Data Entry PEAK TO AVERAGE RATIO PAR P AR no RETURN LOSS RLO Two wire no RL1 Four wire O TLP no RL2 Four wire 16 TLP no RL3 Sine wave no RLU Echo no RIS Low singing no RL6 High singing no RLT Measure all no RL8 600 ohm reference impedance no RL9 900 ohm reference impedance no RLA External standard impedance in no RLB loss Enter hybrid loss yes RESET RST Reset no The HP 4945A goes
197. trument After the POWER ON SELF CHECK has PASSED then proceed to step 5 Press the SET UP hardkey Next press the I O PORT SET UP softkey 4 If you plugged the module into PORT 2 then press PORT 2 SET UP softkey 8 The module should now be iden tified at the top of the screen Press I O MODE softkey 1 until OUTPUT appears in parentheses The HP IB AD DRESS set on softkey 2 is ignored when you set the instrument into this mode Configure your printer for LISTEN ALWAYS mode Your instrument is now ready to print any display by simply accessing the display perform the measurement and then pressing the OUTPUT hardkey When using an RS 232SC printer 1f your printer is already connected to the RS 232C module on your HP 4O45A skip to step 3 nae ho With the HP 4945A turned OFF insert the RS 232C module HP 18163A into one of the ports on the rear panel Connect the cables between the module and the printer Press the LINE button IN to power ON the instrument After the POWER ON SELF CHECK has PASSED then proceed to step 5 Press the SET UP hardkey It HP H9h5A Operation 6 Next press the I O PORT SET UP softkey 4 If you plugged the module into PORT 2 then press PORT 2 SET UP softkey 8 The module should now be iden tified at the top of the screen T Press I O MODE softkey 1 until OUTPUT appears in parentheses 8 Set up softkeys 2 through 7 to reflect your situation Your instrum
198. trument and the manual should be reviewed for safety markings and instructions before operation INSTRUMENTS COVERED BY THIS MANUAL Attached to the instrument is a serial number plate The serial number is in the form 0000A00000 It is in two parts the first four digits and the letter are the serial prefix and the last five digits are the suffix Ihe prefix is the same for all identical instruments it changes only when a change is made to the instrument The suffix however is assigned sequentially and is different for each instrument The contents of this manual apply to instruments with the serial number prefix listed under SERIAL NUMBERS on the title page An instrument manufactured after the printing date of this manual may have a serial number prefix that is not listed on the title page This unlisted serial number prefix indicates the instrument is different from those described in this manual The manual for this newer instrument is accompanied by a yellow Manual Changes HP h9h5A General Information supplement This supplement contains change information that explains how to adapt the manual to the newer instrument lo keep this manual as current and accurate as possible Hewlett Packard recommends that you periodically request the latest Manual Changes supplement Free copies of the supplement are available from Hewlett Packard For information concerning a serial number prefix that is not listed on the title page or in the
199. trument attempts to go on with the tests An example error code display is shown below POWER ON SELF CHECK ERRORS 008 013 113 213 ho 605 606 700 Etc The error codes are three digits and are divided into several error groups as show below Error Code Groups OXZ ROM checksum errors 1X4 ROM location code errors 24k ROM revision code errors 3XX RAM write read errors UXX System peripheral hardware errors 5EX System IRQ line errors 6XX Receiver digital hardware errors TAX Analog hardware errors 8XX Interface errors port 1 OXX Interface errors port 2 Following is amp summary of the self check error codes a description of each circuit tested and the possible failure Mainframe Error Codes Code Circuit tested failure 000 All U60h System start up ROM bad checksum 001 A12 U100 Main ROM 1 6000 9FFF bad checksum 002 A12 U200 Main ROM 2 A000 DFFF bad checksum 003 A12 U300 Bank 1 ROM 2000 SFFF bad checksum 00h Ale U400 Bank 2 ROM 2000 5FFF bad checksum 005 A12 U102 Bank 3 ROM 2000 5FFF bad checksum 006 A12 U202 Bank 4 ROM 2000 5FFF bad checksum HP h9hl5A Operating Verification 007 U12 U302 Bank 5 ROM 2000 5FFF bad checksum 008 U12 U105 Bank 6 ROM 2000 5FFF bad checksum 009 U12 U20h Bank 7 ROM 2000 5FFF bad checksum 011 A10 U607 Receiver ROM 1 E000 FFFF bad checksum 012 A10 U507 Receiver ROM 2 C000 DFFF bad checksum 013 A10 U
200. ttended Another HP 4945A can be used as the slave or any existing TIMS that has tne master slave function such as HP h945A and HP hO9hhA can be used HP IB Hewlett Packard Interface Bus The HP IB is Hewlett Packard s implementation of the IEEE Standard 488 1978 For a description of the operation of the bus refer to Chapter V of this manual HP Ughsa General Information HP IL Hewlett Packard Interface Loop Ihe HP IL is a two wire loop Communications over the loop is asynchronous and serial with the data traveling from one device to the next around the loop in only one direction In this configuration each device receives the message acts up on it if required and retransmits it to the next device until the message returns to the originator For further information refer to Chapter VI of this manual RS 232C The RS 232C interface allows the HP 4945A to be controlled remotely from an external device that is configured for RS 232C serial communications The interface also allows the HP UQ4SA to control other RS 232C devices such as printers For further information refer to Chapter VII of this manual ACCESSORIES The following accessories are available and can be ordered through your local HP Sales and Service Office The addresses are located at the back of this manual HP IB Interface HP 18162A RS 232C Interface VT HP 18163A HPSIL nons uu VeRO y dgio HP 18165A HP IB Cable 1 metre iXacd e
201. turn loss measurements made with a band limited noise signal Sine wave return loss is measured by transmitting a single frequency and then measuring the difference between the transmitted frequency and the received frequency A series of single frequencies can also be transmitted by using the SINE WAVE SWEEP function of the HP h9l54A Return loss measurements require a quiet termination at the distant end of the circuit The result of a single frequency return loss measurement must specify the measure ment frequency Return loss as a measure of impedance match is usually specified as the minimum for any frequency within a specified band Average return loss over a specified band of frequencies may be measured using a sweep frequency The average return loss over the band is a power average noise signal RESPONSE DB FREQUENCY Hz Figure 4 23 Filter Shapes for ERL SRL low and SRL high 4 31 HP 4945A HP IB Operation CHAPTER V HP IB OPERATION Model 18162A INTRODUCTION The HP 18162A interface allows remote control of the HP 4G45A with an external con troller on the HP IB bus The HP IB interface is Hewlett Packard s implementation of the IEEE Standard 488 1978 Normal Mode In normal operation commands from the controller are sent to the HP 18162A Inter face where they are converted into keystroke sequences to set up the HP OLSA Data from the HP h9h5A is sent to the interface and then to the controller
202. ude and Phase jitter Measure All 2 wire Hybrid loss 00 0 Normal Stopped 8 per sec 15 min 4 dB step 68 dB threshold 20 degrees 10 dB gain hit Reference impedance 600 Default values 7 0 0 0 6 0 13 0 29 0 Default values 304 KON 1004 2804 3004 2713 OFF Level 3 Monitor Receiver Beep ON 5 10 HP h9h5A HP IB Operation Table 5 2 HP IB Messages and HP 4945A Responses con t Message Device clear Definition and Response returns the HP 4945A to the same state as selected device clear with the following exceptions Menu Transients Mode TRMT RCV switch Remote REN Local GTL Local Lockout LLO Clear Lockout Set Local Require Service Level Frequency Count is continous HP hO9hhA or Normal remains the same TRMT RCV Causes the listening device s to switch from local front front panel control to remote program control This mes sage remains in effect so that subsequent devices ad dressed to listen go into remote operation The Remote Enable command REN with the HP h9h5A listen address puts the HP 4945A in the remote state Clears the remote message from the listening devices and returns the devices to local panel control The Go To Local command GTL with the HP h9h5A listen address puts the HP 4945A in the local state Prevents the device operator from manually inhibiting remote program control The Local Lockout command LLO puts the H
203. uencies are transmitted dB indicates more loss and dB indi cates less loss relative to the reference frequency 3 2h HP h9h5A Operation Gain Slope Measurement L0 Select the GAIN SLOPE measurement softkey 1 If the transmitting test set is not an HP 4ol5A then the transmitter operator must transmit the tones loh Hz 1004 Hz and 2804 Hz individually The receiving HP 4945A will recognize each of the frequencies and display the relative level to 1004 Hz on the screen Note The transmitted frequencies can be sent in any order but the relative level dB cannot be calculated until 1004 Hz is sent As soon as the receiver recognizes 100h Hz it displays the relative levels of the tones it has previously received if any The measurement is continuously updated using the last 1004 Hz reference HP h9h5A Operation NOISE Description The noise measurements which can be performed with the HP 4OL5A are Noise with Tone Signal to Noise Ratio Message Circuit Noise Noise to Ground Single Frequency Interference 9 e Along with these measurements there are five filters which can be selected They are C message 3 kHz flat 15 kHz flat Program 50 kBit To enter the noise menu press the TEST SELECT hardkey and then the NOISE softkey 2 The following menu will appear 09 28 83 10 48 RM NOISE WITH TONE 28 dBrn NOISE WE E WITH TOHE SIGNAL _T0 NOISE HESSAGE CKT NOISE NOIS
204. uency shift in the test signal This measurement is not valid when on looped around carrier facilities since the frequency shift in one direction near end to far end may be cancelled by the frequency shift in the other direction far end to near end GAIN SLOPE This is a measurement of the loss of received level versus frequency Gain slope is the measurement of the received level at 404 Hz 1004 Hz and 280h Hz Gain slope is calculated by taking the difference between levels at 2804 Hz and 1004 Hz This measurement determines the usable bandwidth of the voice channel To make this measurement the transmitter automatically steps through 1004 Hz 404 Hz and 2804 Hz at 2 seconds per step The frequency received must be within or 26 Hz in order to be displayed on the CRT The gain slope or relative loss will then be displayed after the 1004 Hz reference is measured The loss at 404 Hz and 2804 Hz will be displayed once all three frequencies have been received The gain slope measurement runs continously 4 1 HP h9h5A Measurement Principles The SF single frequency SKIP setup softkey is provided to automatically prevent the test set from transmitting frequencies within the range of 2450 Hz to 2750 Hz This feature is used to prevent loss of voice channel connection when transmitting over a dial up network incorporating single frequency signaling units NOISE MEASUREMENTS The noise measurements determine the interfering effect
205. ure 4 20 as centered at 1380 Hz is suppressed and the lower tone pair is doubled in power This allows the channel to be checked with a test signal of the same power Without the two tone pairs being generated the intermodulation process as measured by the HP 4945A does not occur The receiving TIMS looks for the second and third order products but since these are not present the measured received signals consist of noise The second and third order products as measured with the two tone pairs may then be corrected accordingly to achieve accurate values PEAK TO AVERAGE RATIO MEASUREMENT The peak to average ratio P AR mode allows measurement of the channel dispersion spreading in time of signal amplitude due to transmission imperfections The test signal has a peak to average ratio and a spectral content that approximates a data signal As the P AR signal traverses a dispersive medium the peak to average ratio Will deteriorate Then by measuring the peak to average ratio at the receiving end a simple measure of dispersion is obtained Figure 4 21 illustrates the frequency spectrum of the transmitted P AR test signal and Figure h 22 illustrates the signal envelope 4 28 HP h9h5A Measurement Principles The P AR rating is a single number rating of the fidelity of a channel and is a Weighted measure of the total attenuation phase distortion and noise The P AR rating is derived by comparing the P AR of an ideal signal with the P
206. ver termination impedance The selections it cycles through are 135 600 900 and 1200 ohms Select the impedance that matches the line to which the receiver is connected Set this softkey to TERM if the instrument is to be used to terminate the receive line If the instrument is to bridge across the receive line select BRIDGE When the receiver is bridged it presents a high impedance to the line This ensures that the test set will not disturb the circuit which is under test Turn SF SKIP ON if transmitting over a dial up network where single frequency signalling units are used SF SKIP prevents the instrument from transmitting frequencies between 2450 to 2750 Hz This softkey turns the VOICE BAND LIMIT function ON or OFF When ON it limits the high end output frequency to 3904 Hz and sets the current output frequency to 1004 Hz This is used on N3 carrier facilities to prevent interference with 4 kHz pilot tones Not Used Not Used Not Used Transmitter and Receiver Set Up When in Master Slave In master slave the slave s configuration can be set at the master unit If you are configured for master slave operation then when the TRMT RCVR SET UP softkey 2 is pressed the additional choices shown below will appear Set each of these to the appropriate setting Note These keys will not appear when operating with an HP 4943A or an HP 4OULA slave unit SLAVE TRMT 6 This softkey sets the slave unit s transmitter IMP terminati
207. xs HP 10833A RS 232C Terminal Cable HP 132h2N RS 232C Modem Cable HP 13242G 36 inch 310 to 310 Cable HP 15513A Rack Mounting Kit 19 inch HP 18169A Soft Carrying Case 608 6 HP LOL TOA 23 inch Rack Adapter HP 18176A Rugged Transit Case e HP 9211 2650 OPTIONS The following option is available and can be ordered through your local HP Sales and Service Office The addresses are located at the back of this manual Service Manual Kea aseo sans Option 915 100 200 Volt Operation Option 001 i 3 HP 4955A General Information GENERAL Power Requirements Dimensions excluding feet Weight Operating Environment invertaced gs IB Arena ies s vede MOT E E S EA ere RS 232C Capabilities HP IL Capabilities Termination Impedance receiver and transmitter Hold Circuits Return Loss receiver and transmitter Table 1 1 Specifications 15 230 Vae 11 48 to 63 Hz 150 watts maximum we Height 18 4 cm 7 25 in Width 45 1 em 17 75 in Depth 48 9 cm 19 25 in 15 Kg 33 lbs Temperature 0 to 509 C 4329 to 122 F p Humidity 10 to 90 non condensing Altitude up to 4600 m 15 000 ft Warm up time 5 minutes for stated accuracy ear HP IB E 88 RS 232C HP IL AN2 SRL co Lh 233 SRL EE IT per DIO nr Bit Rates 50 75 110 150 300 600 1200 24

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