VMM860AG User Manual
Contents
1. indicates an invalid channel setting or other conditions that would cause the unit to operate on an invalid channel The RF output is switched off for flashing ERROR conditions F2 AUDIO Level Control The setting of this screwdriver adjustment determines the aural carrier deviation Clock wise rotation increases the carrier deviation F3 VIDEO Level Control The setting of this screwdriver adjustment determines the video modulation level Clockwise rotation increases the modulation depth F4 Channel Number Switch Sets the desired operating channel for standard CATV channels 02 through 135 or Broadcast TV channels 02 through 69 See also Item F5 which sets the type of channel CATV or Broadcast TV and sets the leading 1 for CATV channels 100 through 135 CAUTION USE AN INSULATED SCREWDRIVER BLADE WHEN ADJUSTING THE AUDIO VIDEO A V OR RF ADJUSTMENTS THIS WILL PREVENT THE POSSIBILITY OF SHORTING CIRCUITRY TO THE FRONT PANEL IN THE EVENT THAT THE SCREWDRIVER SLIPS OUT OF THE SLOT IN THE PLASTIC SHAFT OF THE POTENTIOMETER F5 Mode Switch Sets the type of channel CATV or Broadcast TV BC TV The first position of the switch 100 sets a leading 1 for CATV channels 100 through 135 See also Item F4 for setting the channel number For example For example Setting for CATV Setting for CATV channel 125 channel 25 Co n Co Co Co Co Co Co CATV CATV CATV j HES CATV TT ES2. 100 TV 100 TV F6 A V Ratio Control This screwdriver adjustment varies the level of the aural carrier over a range from 12 to 22 dB below the visual carrier The aural carrier should be adjusted to approximately 15 dB below the visual carrier normal operation Clockwise rotation increases the aural carrier level F7 RF Output Level This screwdriver adjustment permits decreasing the RF output level a minimum of 10 dB as the control is rotated counterclockwise Set the control for a 45 dBmV output level SPECIFICATIONS 7 RF Frequency Range FCC Frequency Offsets Output level Output Impedance A V Ratio Frequency Stability Intercarrier Frequency Spurious Outputs 5 MHz to 1 GHz In channel C N Broadband Noise VIDEO Input Level for 87 5 Modulation Input Impedance Frequency Response C L Delay Differential Gain Differential Phase AUDIO Input Level for 25 kHz Peak Deviation Input Impedance Pre emphasis Frequency Response S N ratio Total Harmonic Distortion GENERAL DC Power Input Operating Temperature Size Weight 54 to 864 MHz Standard HRC or IRC CATV channels 2 to 135 Broadcast TV channels 2 to 69 Automatic 12 5 kHz 25 kHz or none as required for each channel 45 dBmV minimum 10 dB adjustment range 75 Ohms 8 GB return loss Audio carrier level adjustable from 22 to 12 dB referenced to video carrier level Within 5 kHz 4 5 MHz
3. CATV channel coverage of the VMMB860AG Where an offset is indicated this amount of positive frequency offset is added to the frequency indicated in the middle column As shown this occurs only on channels required to be offset by the FCC HRC or IRC frequencies can be set by means of an internal jumper See Figure 3 No jumper will result in the STD channel plan selection CATV CHANNEL OUTPUT FREQUENCIES 5 CATV CATV BC TABLE 1 CATY 100 Eg Output Channel Visual Carrier Frequency Switch Setting Frequency MHz Offset kHz CATV CATV TT HES 100 TV Output Channel Switch Setting Visual Carrier Frequency MHz Frequency Offset kHz CATV 100 CATV 100 649 25 655 25 661 25 667 25 673 25 679 25 685 25 691 25 697 25 703 25 709 25 715 25 721 25 727 25 733 25 739 25 745 25 751 25 757 25 763 25 769 25 775 25 781 25 787 25 793 25 799 25 805 25 811 25 817 25 823 25 829 25 835 25 841 25 847 25 853 25 859 25
4. dB variation of adjacent channel carriers Aural Visual A V ratios should be held to 15 dB or less The output RF and A V Ratio controls are used respectively to make these adjustments RACK MOUNTING Adequate ventilation is very important in multi channel installations The RMM12 or RMM4 cages should be spaced apart vertically by at least one rack unit 1 75 height wherever possible Some air movement is mandatory in enclosed rack cabinets Excessive heat will shorten component life and modulator perfor mance will be degraded without proper cooling MODULATOR UNITS Fixed channel and or Agile types 100 240 v AS WATTS DC POWER CABLE I O OF GO Q0 D o O0 RF COMBINER SYSTEM OUT Figure 4 POWER SUPPLY REQUIREMENT FREQUENCY CHART This VMM860AG agile modulator requires more current than the fixed channel units Therefore new 12 position rack installations with multiple VMM860AG modulators up to 12 must use the Drake PSM121 or equivalent high capacity power supply module The power supply in the four position rack system can power up to four VMM860AG modulators or any mix of fixed and agile VMM models up to four total modulators The chart on the following page shows the standard
5. 60 dBc measured at 15 dB A V ratio and with modulator output level of 45 dBmV 65 dB typical 4 MHz bandwidth 78 dBc typicial 4 MHz bandwidth 45 dBmV output 0 65 Vp p to 1 5 Vp p Manual gain adjust with front panel control 75 Ohms return loss of 26 dB minimum 20 Hz to 4 2 MHz 1 GB Within 50 nSec of 0 nSec standard or FCC predistortion option 3 maximum 10 to 90 APL 3 maximum 10 to 90 APL 125 mV rms to 2 5 V rms Manual gain adjust with front panel control Greater than 10 K Ohms unbalanced 75 uSec normal defeatable flat by rear panel switch for BTSC baseband stereo compatibility 40 Hz to 15 kHz 1 0 dB referenced to 75 uSec pre emphasis curve 40 Hz to 100 kHz 0 5 dB if pre emphasis is defeated 65cB 1 maximum 12 V 5 at 200 mA 5 V 5 at 350 mA 0 C to 50 C ambient 1 W x 3 5 H x 7 5 D 2 5 cm W x 8 9 cm H x 19 1 cm D 10 7 oz 0 3 Kg Specifications subject to change without notice or obligation 6 BROADCAST TV CHANNEL OUTPUT FREQUENCIES s CATV TABLE 2 BC TV catv TT VHF BROADCAST CHANNELS UHF BROADCAST CHANNELS Channel Number Channel Number Frequency MHz Frequency MHz REAR PANEL CONNECTIONS INTERNAL JUMPERS 3 R5 Fi Norm Figure 2 R1 VIDEO INPUT Connector This is the nominal 1 Vp p baseband video input to the modulator R2 AUDIO INPUT Connector This
6. 8 WARRANTY AND SPECIFICATIONS THREE YEAR LIMITED WARRANTY R L DRAKE COMPANY warrants to the original purchaser this product shall be free from defects in material or workmanship for three 3 years from the date of original purchase During the warranty period the R L DRAKE COMPANY or an authorized Drake service facility will provide free of charge both parts and labor necessary to correct defects in material and workmanship At its option R L DRAKE COMPANY may replace a defective unit To obtain such warranty service the original purchaser must 1 Retain invoice or original proof of purchase to establish the start of the warranty period 2 Notify the R L DRAKE COMPANY or the nearest authorized service facility as soon as possible after discovery of a possible defect of a the model and serial number b the identity of the seller and the approximate date of purchase and c A detailed description of the problem including details on the electrical connection to associated equipment and the list of such equipment 3 Deliver the product to the R L DRAKE COMPANY or the nearest authorized service facility or ship the same in its original container or equivalent fully insured and shipping charges prepaid Correct maintenance repair and use are necessary to obtain proper performance from this product Therefore carefully read the Instruction Manual This warranty does not apply to any defect that R L DRAKE COMPANY deter
7. ER SUPPLY DRAKE DRAKE DRAKE DRAKE DRAKE DRAKE DRAKE DRAKE mae DRAKE DRAKE DRAKE POWER SUPPLY O oof Ba ene an Sand Cil Daa ens On eo y Od Dad Da eee Bad Da Sad Cad E aa Oa o e GHEE GHP oe GET GT ST S on Om Om Om Om Om Om Om Oem orm Orm Orm E On O On On O On ar d Smo Br Bw c 20 20 20 20 20 20 20 20 2 E PO 20 c S S S S S S OH Ow ENE S Or C JE Jit Jit DIC DIC DICO DIC O F Ii 4 POSITION OR VMM860AG and other compatible RACK MOUNT modular units CO o The VMM860AG modulator is a member of the R L Drake 19 Mini Rack Series a professional quality modular headend system designed to optimize rack space An assortment of up to 12 modular units such as the fixed channel series of modulators or agile modulators or compatible audio video products can be racked alongside a single power supply in the Drake model RMM12 12 position rack mount The RMM4 rack mount accepts up to 4 modular units The R L Drake VMM860AG Audio Video Modulator is a high quality vestigial sideband unit with synthesized visual and aural carriers The frequency agile VMM860AG allows front panel pushwheel switch
8. is an unbalanced audio input to the modulator circuits This RCA phono connector input accepts mono audio from 125 mVrms to 2 5 Vrms levels If the MMTS20 stereo encoder is used this input accepts the composite BTSC stereo output of the MMTS20 R3 DC INPUT Connector This 3 pin connector Male accepts the appropriate mating DC power cable R4 RF OUTPUT Connector This is the modulator output R5 AUDIO PRE EMPHASIS SWITCH This switch allows selection of either normal audio pre emphasis or flat audio response For normal mono audio input to the modulator via R2 set switch to NORM position If the MMTS20 BTSC stereo encoder is used set this switch to FLAT and connect stereo audio to the MMTS20 The encoder will in turn connect to R2 INTERNAL JUMPER SETTING STD HRC IRI Figure 3 4 INSTALLATION CONNECTIONS AND CONTROLS All connections to and from each modulator are made through the rear panel Figure 4 illustrates an installation with 12 modulator units combined through a passive signal combiner Additional channels can be added by using additional fixed channel or agile type modulators and either multi port combiners or combinations of two port combiners INSTALLATION NOTES Level adjustment provides optimum performance in multi channel installations The modulator outputs should be checked periodically with a spectrum analyzer to AUDIO INPUTS AC POWER CORD m VIDEO INPUTS maintain a 1
9. mines is due to 1 Improper maintenance or repair including the installation of parts or accessories that do not conform to the quality and specifications of the original parts 2 Misuse abuse neglect or improper installation 3 Accidental or intentional damage All implied warranties if any including warranties of merchantability and fitness for a particular purpose terminate three 3 years from the date of the original purchase The foregoing constitutes R L DRAKE COMPANY S entire obligation with respect to this product and the original purchaser shall have no other remedy and no claim for incidental or consequential damages losses or expenses Some states do not allow limitations on how long an implied warranty lasts or do not allow the exclusions or limitation of incidental or consequential damages so the above limitation and exclusion may not apply to you This warranty gives you specific legal rights and you may also have other rights which vary from state to state This warranty shall be construed under the laws of Ohio DRAKE R L DRAKE COMPANY 230 INDUSTRIAL DRIVE FRANKLIN OHIO 45005 U S A CUSTOMER SERVICE AND PARTS TELEPHONE 1 937 746 6990 TELEFAX 1 937 806 1576 WORLD WIDE WEB SITE http www rldrake com DRAKE is a registered trademark of the R L Drake Company Copyright 2004 R L Drake Company P N 3852469A 10 2004 DRAKE VMM860AG VIDEO MODULATOR 1 12 POSITION RACK MOUNT POW
10. selection of standard CATV channels 2 through 135 or VHF UHF TV channels 2 through 69 Aeronautical channels are offset positive with a tolerance of 5 kHz as required by FCC rules The heterodyne conversion system in conjunction with the use of a SAW filter ensures optimum vestigial selectivity for adjacent channel headends An optional FCC predistortion SAW response is also available for the VMM860AG The modulator is designed to accept any standard audio video source such as NTSC video and audio baseband signals from a satellite receiver TV camera videotape recorder TV demodulator or similar signal source The modulator is designed to accept standard negative sync polarity video at nominal 1 V p p level All level controls are located on the front panel for ease of operation Output level is 45 dBmvV and is adjustable over a 10 dB range Field defeatable audio pre emphasis by means of a rear panel switch allows transmission of BTSC encoded baseband stereo audio signals when used with the Drake MMTS20 stereo encoder 2 FRONT PANEL CONTROLS and INDICATORS DRAKE F 1 VMM860AG YS POWER F2 kis ERROR F3 E e F6 Hav 4D RF F7 __ CATV Po ems AUDIO VIDEO 5j Figure 1 F1 POWER ERROR Indicator Lights when the unit is connected to the required source of DC power via the rear panel DC INPUT connector A flashing condition
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