Sine/Noise Generators - Types 1049 and 1051
Contents
1. Ore THR product data types 1049 and 1051 yunnnsey QL Sine Noise Generators USES Choice of linear and logarithmic frequency sweep Precision ATE signal generators for use in with sweep rates from 0 001 Hz to 999 9 kHz s computer based test systems requiring a high and 0 001 mDec to 2 Dec respectively accuracy low distortion excitation source Single repetitive I 99 and continuous sweep Semi and fully automatic test and calibration of modes with 0 01 to 100 0 s pause between sweeps electrical and mechanical equipment for product design development production and service TOES poimi amplituda memory with altemellc amplitude interpolation for preconditioned test a Swept frequency electro and building acoustic excitation measurements vibration testing of mechanical j 40 character alphanumeric line display for moni components plus audiological research etc toring and setting up of frequency and amplitude a Storage of amplitude weightings for equalizing non sweep parameters etc flat loudspeaker vibration exciter responses etc 9 set ups for recalling frequently repeated excita a Remote control of Level X Y and Graphic tion test and measurement sequences Recorders for synchronous recording of ampli i a Versatile IEEE IEC bus for remote control and tude phase and distortion responses digital output of data ADDITIONAL FEATURES 1049 FEATURES l l l a 0 2 to 200000 Hz sine ge2. 0 2dB at 0 2 Hz and 200 kHz At lower frequencies the am plitude falls by 20 dB per decade but by utilizing the Memory Learn func tion of the Generators to maintain a constant output level of 300 mV or less a flat amplitude characteristic can be maintained at all frequencies down to 0 001 Hz output 502 Chassis Floating Fig 3 BNC Output and Chassis Floating switch of the 1049 and 1051 Sweep Synthesizer The Sweep Synthesizer includes a ramp register which produces a 31 bit output representing the frequency set ting of the Generators The frequency may be set by an input either from the front panel keyboard or via the inter face bus of the Generators For a fre quency sweep however an internal clock signal is used enabling either Linear or Logarithmic frequency sweeps to be chosen with sweep rates from 0 001 Hz s to 999 9 kHz s and 0 001 mDecade s to 2 Decade s re spectively With linear and logarithmic fre quency sweeps six or more complete frequency decades can be covered in a single range The logarithmic sweep range extends from 0 2 Hz up to 200 kHz while the linear sweep range is from 0 001 Hz up to 200 kHz how ever either can be independently set to any lower or upper frequency limit within these ranges if so desired In addition to the above Up Down Up Down Single Re petitive 1 to 99 and Continuous sweeps modes may be ch
3. Besides a ramp register for frequen cy synthesis the Sweep Synthesizer contains an amplitude register for controlling the Output Section Atten uator For manual setting of the output level the amplitude register accepts a numeric input from the front panel keyboard or a digital input applied over the interface bus of the Genera tors The input may be applied direct ly to the amplitude register or if the Memory Learn function is used via the internal memory of the Genera tors In the latter case up to 1024 amplitudes can be stored for success ive frequencies within any desired fre quency range of the Generators and when recalled enable almost any type of single or repetitive amplitude weighted frequency sweep to be gen erated The Memory Learn function is of particular benefit for swept frequency sound and vibration measurements When one of the Generators is em ployed to drive a loudspeaker or vibra tion exciter for example its output level can be weighted according to the dynamic response of the loudspeaker or vibration exciter so that a constant sound pressure or vibration level out put is maintained over the entire fre quency range of interest To save entry of each individual level manually the Memory Learn function includes automatic ampli tude interpolation between consecu tive amplitudes input Alternatively amplitudes may be entered as a volt age signal via the Compressor Inpu
4. I Con troller C 0 Data Ouput Generator frequency output lev el etc plus all front panel control settings Remote Control All functions and instrument front panel settings can be remotely con trolled via the digital interface Amplitude frequency can be set with full resolution in less than 20 ms Binary 30 ms ASCII format Code ISO 7 bit code GENERAL Warm Up lime 20 minutes Temperature Range Operation 10 to 40 C 50 to 104 F Max Humidity 90 RH non condensing at 30 C Electromagnetic Compatibility Complies with Class B Device of the American FCC Rules Power Requirements Complies with IEC 348 Safety Class Il Supply Voltage 100 115 127 200 220 240 V AC 50 to 60 Hz 10 Consumption 50 VA Cabinet Supplied as Model A light weight metal cabinet or Model C as A but with flanges for standard 19 in rack Dimensions Metal cabinet excluding knobs and feet Height 133 mm 5 2 in Width 430 mm 16 9 in Depth 320 mm 12 6 in Weight Type 1049 11 6 kg 25 5 Ib Type 1051 11 1 kg 24 5 Ib ACCESSORIES INCLUDED 1 x Mains Cable 1 x BNC Plug 1x IEEE Std 488 Bus Connector Kit 2 x 250 mA Fuse 2 x 500 mA Fuse Instruction Manual AN 0020 J 0035 seve mn JA 0814 ACCESSORIES AVAILABLE Service Manual Interface Cable 2 m IEC 625 1 25 way to IEEE 48 Interface Cable 2 m IE X Y Recorder Control Cable 1 5 m Level Recorder Control Cable 1 5 m Rack Mou
5. equip Specifications 1049 1 051 SINE GENERATOR Frequency Range 0 2 Hzto 200kHz The generator can be used at frequencies down to 0 001 Hz See Amplitude Linearity Spec Frequency Resolution 1 98 mHz Frequency Stability lt 25 ppm from 10 to 40 C with lt Sppm aging per year Harmonic and Spurious Distortion 96 dB within 20 Hz to 20 kHz lt 85 dB within 0 2 Hz to 100 kHz lt 75 dB within 100 kHz to 200 kHz Phase and A M Noise lt 85 dB measured over 200 kHz range with 5 V output and 1 Hz rejection band centered on output frequency Amplitude Linearity 0 05 dB from 20 Hz to 20 kHz 0 2dB from 0 2 Hz to 200 kHz 3dB limit 0 01Hz with 20 dB decade attenuation slope down to 0 001 Hz GENERATOR OUTPUTS Via BNC sockets on front and rear panel Output Voltage 100 Vto5V RMS selec table to 3 digits with 0 026dB relative atten uator accuracy Output readout based on no load condition Output Impedance 50 Q Grounding Chassis Floating 0 1 V max OUTPUT On Oft Fast lt O 1 ms rise and decay time Slow 30 ms for raising and suppressing output signal 60 dB AMPLITUDE MEMORY 1024 amplitudes can be memorized within any given frequency range and later recalled for successive single or repetitive amplitude weighted frequency sweeps Amplitudes may be input numerically via the front panel push keys digitally via the IEEE IEC interface or as a voltaae input to the 1049 compressor Includes aut
6. limiting and delimiting characteristics of audio recording and reproducing equipment plus studying the dynamic behaviour of loudspeak ers earphones and telephone hand sets For these applications either the random noise or sine output may be employed and the output level swept up and down with a sweep rate be tween 0 01 and 999 dB s As with the Compressor the ampli tude sweep is obtained by utilizing the amplitude register of the Sweep Syn thesizer to automatically step the Out put Section Attenuator of the 1049 In this case however a separate clock signal is applied whose frequency determines the particular sweep rate selected The amplitude resolution of the sweep is better than 0 1 dB Monitoring and Set Up Adjustments Display and Field Entry For convenient setting up and mon itoring of control settings frequency sweep and output voltage limits etc the front panel is furnished witha 40 character vacuum fluorescent line dis play plus a keyboard for selection of set up and operating modes see Figs 6 and 7 Depending on the par ticular set up and operating mode chosen the display is capable of indi cating as many as four control settings simultaneously which also makes it useful for monitoring control parame ters during the course of measure ments Just below the display are four Field Select keys for selecting control set tings to be changed These may be used either to select and set a particu
7. pass filters the two signals are mixed and summed to produce two complementary signals which on an amplitude basis represent each half of the narrow band noise characteristic shown in Fig 5 but with centre frequency of 500 kHz The two signals are then combined and fed to the 500 to 700 kHz mixer stage of the Output Section where they are con verted to a swept frequency narrow band noise output operating over the same sweep range as the sine wave output of the Generator Because of the high crest factor of the narrow band white and pink noise generated by the 1049 the noise is attenuated by 12 dB factor of 4 with respect to the sine output The gener Attenuation 90 10 6 6 4 2 0 2 4 6 810 Bandwidths from centre frequency 8860390 Fig 5 Pass band of the 1 3 16 10 31 6 100 and 316 Hz narrow band noise bandwidths of the 1049 ator automatically accounts for this so that the exact output level in the noise as well as the sine modes is dis played Compressor As an alternative means of main taining a constant output level with a loudspeaker or vibration exciter the 1049 includes a Compressor This en ables a live control signal from an external preamplifier and measure ment transducer to be used to auto matically regulate and weight the out put level of the Generator according to the dynamic characteristics of the loudspeaker or vibration excite
8. CORDER INTERFACE Level Recorder 7 pin DIN socket providing remote control of start stop automatic stop and pen lift X Y Recorder 8 pin DIN socket providing re mote control of pen lift and X deflection Voltage Ramp 0 to 10 V for X deflection 12 bit D A Converter Linearity 10 bit 200 Hz sample frequency Ramp Voltage Limits Lin or Log voltage ramp selectable for either Lin or Log frequency sweep Lin Ramp 0 to 10 V for any lower or upper frequency limit from 0 Hz to 200 kHz or fixed limits of 0 Hz to 200 Hz 0 Hz to 2 kHz 0 Hz to 20 kHz and 0 Hz to 200 kHz Log Ramp 0 to 10 V ramp for any lower or upper frequency limit from 0 2 Hz to 200 kHz or fixed limits of 0 2 Hz to 200 kHz 2 Hz to 2 kHz 20 Hz to 20 kHz and 200 Hz to 200 kHz Amp Ramp 1049 only 0 V to 10 V for any lower or upper amplitude limit from 40 to 140 dByV or fixed limits of 40 to 100 dBuV 60to 120 dBuV and 80 to 140 dBuV Ramp Delay 0 00 to 1 00 s selectable with resolution down to 0 01s IEEE IEC DIGITAL INTERFACE Conforms to IEEE 488 and IEC 625 1 stan dards Connection into an IEC interface sys tern is made using cable AO 0264 or cable A0 0194 and Adaptor A00195 Connection into an IEEE interface system is made using cable AO 0265 Functions Implemented Source Handshake SH 1 Acceptor Handshake AH _ 1 Talker T 5 Listener L 3 Service Request SR 1 Remote Local RL 1 Parallel Poll PP 0 De vice Clear DC 1 Device Trigger DT
9. OG sweep Line Display EN and P al al Front Panel Controls Control Bus ES aaa Freq Bus Freq Bus Fixed 31 Bit 8 Bit Ext Syne x jExt Sy List Digital gt e synthe sizer 100 kHz 100 200 kHz 50 kHz Amplitude Noise anil D von 500 kHz Bus Signal 5 MHz Fixed in y 500 kHz 1 Compressor 7 Noise Svn4 m Input Com Attenuator Bus l Ittiesizer Saad pressor 1049 only 1049 only ten Amp ee T e ane J W tS DSe i L Control Bus J E NamrowBaaddy iva tedaidkPirN oirdee E Output Section Mixes At Micro processor IEEE IEC Interface Control ana 2 Level IEEE IEC Recorder Control Interface a 5 7 MHz Variable A Generator Output 0 2 Hz 200 kHz Fig 1 Simplified block diagram of the B amp K Sine Noise Generator Type 1049 and Sine Generator Type 1051 Outputs levels from 100 BV to 5 V RMS may be chosen to 3 digits permitting either a constant amp litude or an amplitude weighted fre quency sweep to be obtained With the latter up to 1024 amplitudes may be stored which enable the Genera tors to simulate the output of record reproducer pick ups tape heads and electrical circuits etc Also equaliz ation characteristics can be stored for maintaining a constant sound pressure or vibration output with loudspeakers and vibration exciters All functions and parameters may be selected or entered by the front panel pushkeys or via the EEE IEC dig
10. Synchronization Input of the 1049 and 1051 Generators Input socket on the rear panel See Fig 2 For a 5 to 7 MHz variable frequency proportional to the generator output frequency a 31 bit frequency control output from the Sweep Synthesizer is utilized To achieve a wide sweep range while maintaining a high accu racy and resolution the Sweep Syn thesizer output is split into two com ponents The lowest 23 bits are used to produce a 100 to 200 kHz variable control frequency proportional to the Hz and mHz frequency setting of the Generators while the remaining 8 bits are used to produce a 49 9 to 69 9 MHz control frequency propor tional to the kHz setting The respective control frequencies are generated by a digital synthesis and a divide by N phase lock loop They are then summed by another phase lock loop to produce a 50 to 70 MHz control frequency which after application toa 10 1 frequency divider in the Phase Lock Synthesizer is fed to the Output Section where the final stages of frequency conversion take place The use of two phase lock loops for producing 50 to 70 MHz control frequency ensures that phase noise is kept to a minimum Output Section From the Phase Lock Synthesizer the 5 to 7 MHz control frequency is applied to a second 10 1 frequency divider which is included at the input of the mixer stage of the Output Sec tion The output is then mixed with the 500 kHz output of the Master Clock to pr
11. ce Recorder Interface For graphic recording of swept fre quency tests and measurements ana log outputs are available for coupling level or X Y recorders These are shown in Fig 8 and provide the neces sary control voltages for synchronous recording over a maximum of six fre quency decades with either the B amp K Level Recorder Type 2307 or X Y Recorder Type 2308 With X Y Recorders recordings can be made on linearly or logarithmically graduated paper irrespective of which type of frequency sweep is chosen on the Generators Also plotting of for ward and reverse frequency sweeps is possible and for tape recorder and acoustic investigations the X Y syn chronization can be delayed between 0 and 1 s in 10 ms steps to coincide with the arrival of the measured signal For continuous monitoring of measure ments the wide choice of sweep rates of the Generators enable the X Y out put to be used to control an oscillo scope Auxilliary Outputs Supplementing the sine wave and noise outputs of the Generators is a square wave output This provides a 1 mHz to 200 kHz TTL signal corre sponding with the frequency setting of the Generators which will be found ideal for pulse testing of electronic measuring recording and reproducing equipment Also available with the Generators are a fixed frequency 5 MHz anda Interface Bus IEEE Fig 8 The Recorder and Digital Interface connectors of the 1049 and 1051 variable f
12. ent These include the Digital Voltmeter Type 2432 Dig IEEE IEC Interface Cable fe aes FHR cts 6 b L A Voltmeter Sine Generator Phase Meter 2432 1049 1051 2977 Computer S teresen Electronic lpi INe Device under Test ee l as Fig 10 Automatic test arrangement for frequency response measurements amplitude and phase on electronic equipment Using their inter nal memory for preconditioning the 1049 and 1051 Generators can simulate a record pick up tape head preamplifier equalization network output etc ital Phase Meter Type 2977 High Resolution Signal Analyzer Type 2033 and Dual Channel Signal Analyzers Type 2032 and 2034 all of which are especially designed for a wide variety of response measurements and fre quency analyses For storage and documentation of results the Digital Cassette Recorder Type 7400 plus Graphics Recorder and Plotter Type 2313 and 2319 are available Some typical examples of the use of these instruments with the Generators are shown in Figs 10 to 12 As with the Generators all the digital equipment mentioned can be controlled via a computer or purpose built system controller which features an IEEE IEC interface This makes them ideal for use in laboratory pro duction and environmental testing where very many performance tests and calibration checks have to be carried out which are of a repetitive nature Here it is useful that tests are carried out on an automatic ba
13. it and sweep rate selected Minimum single sweep time is 8 ms for repet itive Up Down sweeps and 62 5yus for sweeps including pause or single sweeps in one di rection LINE DISPLAY 40 character vacuum fluorescent line dis play with 4 display fields for entry and stor age of generator control settings as well as simultaneous monitoring of generator output frequency output voltage compressor volt age etc TEST PROGRAMMES Non volatile memory for storage of front pan el control settings Enables 9 user defined control sequences to be stored and instantly recalled for electronic electro acoustic and vibration test work For continuous storage of control settings the Generators must be sub jected to 2 to 4 hours use per week AUXILIARY INPUTS OUTPUTS Via separate BNC sockets on rear panel Square Output TTL square wave output of generator frequency from 1 mHz to 200 kHz Ext Sync In For phase locking internal clock with external signal source Input Freq 10 MHz down to tenth sub har monic Input Voltage 0 6 to 30 V Peak to Peak Tuning Range 100 ppm Ground Chassis Floating 0 1 V max Fix Freq Out 5 MHz square wave output reference frequency Output Voltage 0 6 V Peak to Peak Output Impedance 200 Q Var Freq Out User selected 5 to 7 MHz or 50 to 70 MHz output depending on generator frequency Output Voltage 0 6 V Peak to Peak Output Impedance 25 Q Sweep Start TTL output for trigger ing record RE
14. ital interface bus of the Generators In addition there is an analogue speeder knob for fast and precise continuous adjustment of parameters Front panel set up conditions are in dicated on a 40 character line display from which as many as four functions and their individual parameters may be monitored simultaneously If desired nine sets of front panel set up conditions may be stored and instantly recalled for performing fre quently used excitation test and mea surement sequences as is normally called for in service and production testing of products For automatic plotting of swept frequency measure ments and analyses special provision is made for synchronizing level and X Y recorders Alternatively where an IEEE IEC system controller is used for automatic control of the Genera tors they may be coupled with a digi tal plotter In addition to the above the Type 1049 has a number of extra facilities These include a logarithmic amplitude sweep as well as narrow band ran dom white and pink noise outputs Also a compressor circuit is built in as an alternative means of obtaining a constant sound or vibration level out put when a loudspeaker or vibration exciter is employed with the genera tor In this case however external feedback is employed to provide ac tive regulation of the generator output which has the benefit that it automati cally takes into account the response of the exciter under actual tes
15. lar control setting directly enabling a linear sweep to be changed to a loga Sine Noise Generator Type 1049 z 200 0kHz Fig 6 Vacuum fluorescent line display plus the field select and speeder controls of the 1049 and 1051 Fig 7 The Setup Mode Sweep and Signal keys of the 1049 rithmic sweep for example or for in creasing the number of digits by which the frequency may be entered using the numeric pushkeys on the right of the front panel Alternatively the fre quency and amplitude limits may be altered by employing the Speeder knob which is located beneath the Field Select keys The Speeder emulates the function of the coarse and fine tuning knobs of analog types of generator Turning the knob a fraction to the left or right gradually decreases or increases the displayed value for the function se lected with the Field Select keys while a proportionately larger turn increases the speed at which the displayed value is altered Operating Set Ups When first switched on the Genera tors are automatically set to the con trol settings selected during previous use The settings are stored in a con tinuous memory which is capable of storing 9 complete sets of front panel settings or setups so that a number of exciter control programmes may be kept on hand for performing frequent ly repeated swept frequency tests and measurements The individual setups may be in stantly recalled whenever desired si
16. mply by entering their set up num ber Provided that the memory back up battery is kept charged by subject ing the Generators from between 2 to 4 hours use per week then the set ups may be retained indefinitely See the Specifications section If required an entire setup may be copied in another setup so that only a limited number of control settings changes need be made to obtain a new setup suited to a specific test or task Where more than 9 setups are re quired they may be stored externally using a digital tape or disk station and input over the digital interface of the Generators Interfacing Digital Interface The digital interface of the 1049 and 1051 conforms with the IEEE Std 488 1978 and is fully compatible with the IEC 625 1 standard It may be interconnected with as many as 15 separate instruments at one time thus enabling numerous fully integrated ATE automated test equipment systems to be built which may be operated via a desk top calculator computer or purpose built controller The interface has a full Talker T5 and Listener L3 capability permit ting remote sensing and selection of the generator controls plus printing of the control status As with other B amp K instruments the interface accepts easy to interpret acronyms as well as complete control names for com mands thus enabling users to setup their own fully automatic control sequences with the minimum of pro gramming experien
17. nd 160 mV Up Sweep 1 25 mV 20 mV and 320 mV Sweep Limits Selectable to 4 digits in whole amplitude range with 0 1 dBuV resolution COMPRESSOR Compression 118dB max for sine and noise modes Speed 0 3 1 3 10 30 100 300 and 1000 dB s Input Attenuator 0 10 to 2 50 V accuracy 1 3 digit 0 01 V resolution Input Detector RMS Freq Response 2 Hz to 200 kHz 0 2 dB WORLD HEADQUARTERS DK 28 50 N rum Denmark Telephone 452800500 Telex 37316 bruka dk Fax 452801405 Australia 02 450 2066 Austria02235 7550 0Belgium02 2429745 France 1 645720 10Federal Republicof Germany 04106 4055 Great Japan03 438 076 1Republic of Korea Sweden 08 71 12730 Brazil 011 246 8149 246 8 66 Canada 514 Britain 01 954 02 554 0605 Norway 02 787096 Portugal Switzerland 042 65 1161 Taiwan 0Z 7139303 USA 695 8225 Finland 90 80 17044 2366 Holland 03402 39994 Hong Kong 5 487486 Italy 02 5244 141 1 6592561659280 Singapore 2258533 Span 91 2681000 508 481 7000 Local representativesand service organisations world wide
18. nerators with frequency a Narrow band random white and pink noise modes resolution down to 1 mHz and clock stability a Logarithmic amplitude sweep with sweep rates better than 5 x 1 0 year from 0 01 to 999 dB s a Calibrated output from 100 uV to 5V with less 118 dB compressor circuit for active control of than 96 dB harmonic and spurious distortion sound or vibration level at exciter output a Six decade frequency sweep in one continuous a Automatic learn mode for amplitude memory via range with selectable lower and upper limits compressor The B amp K Types 1049 and 1051 are two microprocessor based sine genera tors which combine today s needs of increased spectral purity frequency resolution and stability with ease of use and versatility Their wide fre quency coverage from 0 2 Hz to 200 kHz with amplitude linearity and frequency resolution of 0 05 dB and 1 mHz make them suitable for nu merous applications in electronic engi neering as well as in acoustics and vibration measurements Linear and logarithmic sweep ranges each with Fr J 1 0000kHz 100 OdBuv core their own user presettable lower and upper limits may be chosen including extended linear sweeps from 0 001 Hz to 200 kHz Single repetitive and con tinuous sweep modes are also included and the time for each individual sweep is automatically calculated and dis played Sine Generator Type 1051 BP 0587 14 Speeder L
19. nting Flanges AO 0264 AO 0265 marn AQ 0034 AQ 0035 KS 0023 Additional Specifications 1049 NOISE GENERATOR Generator Type Pseudo Random Distribution Symmetrical Gaussian tude distribution up to 4 5 Line Spacing and Sequence Length 1 137 wHz ampli Line Spacing 11 37 nHz 113 7 nHz Sequence 4 Length 24434h 2443h 244 3h T07029GB1 Spurious Distortion As for Sine Generator 12 dB Spectral Flatness 0 5 dB within freq range Output Voltage As for Sine Generator 12 dB Narrow Band Random Mode Centre Frequency As for Sine Generator Noise Bandwidth 1 3 16 10 31 6 100 and 316 Hz Actual 3dB bandwidth 4 7 nar rower than noise bandwidth Filter Types 3 pole Butterworth White Noise Mode Frequency Range Limits Lower 2 20 and 200 Hz 0 5 dB 1 4 14 and 140 Hz noise limit The actual 3dB lower limit is 4 6 greater 2 20 and 200 kHz 0 5 dB 2 8 28 and 280kHz noise limit The actual 3dB upper limit is 4 6 less Filter Type and Ripple d pole Chebishev lt 0 1 dB ripple Pink Noise Mode As for White Noise Mode but with 10 dB decade attenuation above 2 20 and 200 Hz lower limits AMPLITUDE SWEEP Rate 0 01 to 999 dB s with resolution down to 0 1 dB and 2 to 2 4 accuracy Switching Amplitude sweep and compress or regulation causes small transients due to range switching at the following levels Down Sweep 612 5 uV 10 mV a
20. oduce a sine wave signal whose frequency corresponds directly to the frequency indicated on the dis play of the Generators For removing unwanted side band components in the mixed signal a 280 kHz low pass filter is employed Before application to the outputs of the Generators the filtered sine wave signal is fed to an attenuator and amplifier for amplitude conditioning The output attenuator gives an overall attenuation of 16 bits enabling the fraction and exponent of the output level to be accurately set within 3 digits from 100 nV to 5 00 V RMS via the front panel controls and interface bus of the Generators The Output Amplifier provides two low impedance signal outputs which are made available at a BNC socket on the front and rear panels These may be matched with 50 Q signal lines and to suit different test system grounding requirements may be isolated or con nected to chassis by means of a slider switch on the rear panel See Fig 3 In the design of the Generators particular attention has been paid to obtaining very low signal distortion and good amplitude linearity As indi cated in Fig 4 the maximum harmonic and spurious distortion is guaranteed better than 96 dB at frequencies be tween 20 Hz and 20 kHz with second and third harmonic distortion compo nents typically 110dB down at 1 kHz The amplitude linearity of the out put is better than 0 05 dB at fre quencies between 20 Hz and 20 kHz decreasing to
21. omatic amplitude interpolation between consecutive amplitudes input FREOUENCY SWEEP Linear Logarithmic with or without amplitude weighting from amplitude memory Sweep Limits from 0 2 Hz to 200 kHz selec table to 4 digits In extended range 0 001 Hz to 200 kHz linear sweep The limits will be reached within the resolution of the program med stop frequency 0 001Hz Sweep Rate Linear 0 001 Hz s to 999 9 kHz s selec table to 4 digits with 2 15 accuracy Logarithmic 0 001 mDec s to 2 000 Dec s 2715 0 2 selectable to 4 digits with per Dec s accuracy Sweep Resolution Linear imHzatrate lt 4 768 kHz s or lt 0 244 Hz at rate gt 4 788 kHz s Logarithmic lt 1mHzatrate lt 8 089m Decsor frequencies lt 1 kHz 0 244 Hz outside the above limits Sweep Modes Up Down Up and Down Sin gle Repetitive 1 99 times and Continuous are selectable Amplitude Weighting 1024 amplitude levels can be played back during the frequency sweep See AMPLITUDE MEMORY Spec Sweep Pause 0 00 to 100 0 s pause between repetitive sweeps selectable with 10 or 100 ms resolution and 1 ms accuracy Pause Output Output may be set On or Off between repetitive sweeps Control Limits Sweep on may be individually preset to reference or any preset lower and upper frequency or amplitude limit dependent on sweep type Sweep lime Computes and displays time for single sweep between particular lower and upper lim
22. osen Also there is a Pause function whereby a preset delay of between 0 and 100 s may be included between each consec utive sweep Distortion Level Hy TH A ox 2 Hz and Harmonic HH eS a hi 20 Hz Guaranteed Max Distortion 5 V Output No Load Condition Hp H aee t a t oT CS t 3 Harmonic H 4 t it HA ae T T f 200 Hz 2k Frequency Hz 0 02 0 01 C S t 0 003 7 t a Q a 0 001 g c Q 9 Q a 0 0003 0 0001 20k 200 861060 Fig 4 Typicaland maximum guaranteed distortion levels produced by the 1049 and 1051 Generators 5 V output no load condition in the frequency range from 2 Hz to 200 kHz A convenient feature is that the Generators automatically compute the time for a single sweep The sweep time is indicated directly on the front panel display and automatically takes into account the particular frequency limits and sweep rate chosen With single and repetitive Up Down sweeps a minimum sweep time of 8 ms can be achieved while with sweeps including pause or single sweeps in one direc tion sweep times as short as 62 5 ys are possible Because the frequency sweep of the 1049 and 1051 is rate based a higher sweep accuracy can be maintained With generators which are program med with respect to time the sweep accuracy is generally lower partic ularly with logarithmic sweeps Amplitude Memory
23. r under actual test conditions The Compressor comprises an Input Attenuator and RMS Detector fol lowed by a VCO and Voltage Compar ator The VCO is used to produce a variable frequency clock signal which is proportional to the rate of change of the input signal and is fed to the am plitude sweep register for automatic control of the Output Attenuator The decision as to whether an increasing or decreasing amount of compression is needed to maintain a constant excita tion level is made by the Comparator which actuates the up down input of the amplitude register The Compressor is equally adept at regulating the random noise as well as sine wave outputs of the 1049 and gives no regulation error when dwell ing at a single frequency In both modes regulation over a 118 dB range is achieved relative to a maximum output level of 5 V RMS The amount of compression is ad justable over a wide range using the Input Attenuator and either the input level or the amount of compression can be monitored directly on the 1049 For regulating low frequency signals without distorting the signal wave form as well as counteracting excita tion peaks of loudspeakers and vibra tion exciters there is a choice of eight compressor speeds ranging from 0 3 to 1000 dB s Amplitude Sweep Also available with the 1049 isa logarithmic amplitude sweep This may be chosen in place of a frequency sweep and is useful for investigating the electrical
24. requency 6 7 MHz 50 70 MHz user selected output which may be used as clock references for external equipment Synchronization Input For locking the internal clock of the Generators with an external source a Synchronisation Input is provided which accepts a 10 MHz signal or an appropriate sub harmonic See Specifications Examples of Use Because of their high performance capability and extreme operating flex ibility the Sine Noise Generator Type 1049 and Sine Generator Type 1051 can be used for a very wide range of applications Ext Sync In Chassis Fix Freg Out 5MHe int selected Fig 9 The Fixed and Variable Freq Out puts plus the External Synchroni zation Znput of the 1049 and 1051 Their wide frequency and dynamic ranges high accuracy resolution and stability plus extensive remote con trol possibilities via a standard IEEE IEC digital interface make them an ideal ATE signal source for electronic design and development work quality control production test and service of a wide variety of electri cal products In addition the noise output and compressor facilities of the 1049 will find extensive applications in electro acoustic and building acous tic investigations as well as in vibra tion testing of mechanical components and structures For use of the 1049 and 1051 as part of a larger measurement system Br el amp Kj r markets a range of analogue and digital equipm
25. sis us ing a computer or system controller to control the entire test setup Also a computer can be used for reformatting measured data to produce a hardcopy readout of frequency phase and am plitude responses etc with a graphics recorder or plotter In more advanced systems a computer may be used to decide on whether test results are within acceptable limits as well as to diagnose faults For further details on the B amp K equipment mentioned please consult the B amp K Short Form or Master Cata logues Sine Generator 1049 1051 Electronic Device under High Resolution Signal Analyzer IEEE IEC Interface Cable Graphics Recorder 2313 Application 2033 Package BZ 7002 860394 1 Fig 11 Harmonic distortion measurements using the 1049 or 1051 Generator with the 2033 High Resolution Signal Analyzer IEEE IEC Interface Cable Sine Noise Generator 1049 Electronic Device under Test Signal Analyzer koni S ee Computer Dual Channel 2032 2034 Lest se s Graphics Plotter 2319 861062 Fig 12 Automatic test arrangement using the 1049 Sine Noise Generator with the 2032 or 2034 Dual Channel Signal Analyzer for transfer function and distortion measure ments on electronic equipment Using the amplitude sweep function of the 1049 the attach and release time of compressor expander circuits ment may be measured and other non linear
26. t condi tions Description A simplified block diagram of the B amp K Generators Types 1049 and 1051 is shown in Fig 1 They have 6 main sections namely a Master Clock a Digital Frequency Synthesizer a Phase Lock Synthesizer a Sweep Syn thesizer and an Output Section all of which operate under the guidance of a Microprocessor Section which takes care of the user communication via the front panel controls and IEEE IEC interface of the Genera tors In addition Type 1049 features a Noise Generator and Compressor which greatly increase its range of applications especially for acoustic and vibration measurements Frequency Synthesizer The Generators employa hetero dyne synthesis technique where a 500 kHz fixed frequency is mixed with a 500 to 700 kHz variable frequency to produce an 0 001 Hz to 200 kHz swept frequency sine wave output with frequency resolution of 1 mHz The 500 kHz fixed frequency is ob tained from a Master Clock while the 500 to 700 kHz variable frequency is derived from the 5 to 7 MHz output of a Phase Lock Synthesizer The Master Clock is based on a sta ble 10 MHz crystal oscillator whose relative accuracy is transferred to the output frequency If an even greater accuracy is required the internal osc illator can be phase locked with an external reference which may be cou pled to an External Synchronization Ext Sync In A i 10 MHz Chassis Floating Fig 2 External
27. t of the 1049 Additional Features Type 1049 Noise Generator In the Sine Random Generator Type 1049 wide band pseudo random noise of very even spectral density is generated by two long shift registers followed by a low and high pass filter The noise signal has a symmetrical gaussian amplitude distribution up to 4 5 with upper frequency limit line spacing and sequence length depend ing on the shift register clock frequen cy See Specifications By selecting the appropriate 0 5 dB lower and upper frequencies of the filters nine combinations of white noise can be obtained ranging from 2 20 or 200 Hz up to 2 20 or 200 kHz The filters are 3 pole Chebi shev types giving less than 0 1 dB ripple and an 18 dB octave low and high frequency roll off For a pink noise output over the same frequency ranges the white noise signal is fed through a 3 dB octave filter before being applied to the attenuator and amplifier stages of the Output Sec tion For a swept frequency narrow band noise output the white noise signal is fed to a balanced modulator circuit This produces two DC to 1 25 kHz noise signals with relative phase of 0 and 90 which are applied to two identical low pass filters The filters are 3 pole Butterworth type which have a high frequency attenua tion slope of 18 dB octave with selec table cut off frequency of exactly half the particular noise bandwidth chosen on the Generator From the low
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