4 WARRANTY AND SPECIFICATIONS
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: 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.
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 determines is due to: specifications of the original parts.
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.
SPECIFICATIONS
RF
Frequency Range:
VMM600-
VMM860-
Output Level:
Output Impedance:
A/V Ratio:
Frequency Stability:
Intercarrier Frequency:
FCC Frequency Offsets:
Spurious Outputs:
54 to 1000 MHz
Broadband Noise:
54-600 MHz.
Factory set to one of the following channels:
Cable Channels 1-86, 95-99 or
UHF-TV Channels 14-35.
600-864 MHz.
Factory set to one of the following channels:
Cable Channels 87-135 or
UHF-TV Channels 36-69.
+45 dBmV, minimum.
Adjustable over a 12 dB range.
75 Ohms, return loss of 12 dB.
Audio Carrier -10 to -22 dB referenced to video carrier, adjustable.
+ 5 kHz (Visual Carrier).
4.5 MHz, ±50 Hz.
All aeronautical channels are offset positive.
-65 dBc, measured at -15 dB A/V ratio and with modulator output level of +45 dBmV.
-95 dBc, referenced to video carrier.
(4 MHz BW and +36 MHz offset).
VIDEO
Input level for 87.5% modulation:
Input Impedance:
Frequency Response:
Video S/N:
1 Vp-p +3 dB, manual gain adjust with front panel control.
75 Ohms, return loss of 18 dB minimum.
20 Hz to 4.2 MHz, +1 dB.
65 dB minimum, luminance weighted.
VIDEO (continued)
Differential Gain:
Differential Phase:
C/L Delay:
+3% (10 to 90% APL).
+3 degrees (10 to 90% APL).
Within 50 nSec. of 0 nSec.
(standard), or
FCC predistortion, (option).
AUDIO
Input Level for 25 kHz
Peak Deviation:
Input Impedance:
Pre-Emphasis:
Frequency Response:
4.5 MHz Intercarrier Stability:
Total Harmonic Distortion:
Hum and Noise:
100 mV to 2.5 Vrms;
manual gain adjustment
with front panel control.
10 K Ohms, unbalanced.
75
µ
S. (Defeatable via
jumper setting for BTSC
baseband stereo compatibility).
40 Hz to 15 kHz, +1.0 dB referenced to 75
µ
S pre-emphasis curve.
(40 Hz-100 kHz ±0.5 dB if pre-emphasis is defeated).
+50 Hz, frequency synthesized.
0.5% Maximum.
-65 dB minimum, referenced to 25 kHz peak deviation.
GENERAL
DC Power Input:
Operating Temperature:
Size:
Weight:
+12 VDC @ 150 to 220 mA, channel dependent.
+5 VDC @ 75 to 100 mA, channel dependant.
0°C to +50°C.
1"W x 3.5" H x 7.5"D.
11 oz.
Specifications subject to change without notice or obligation.
®
VMM 600/VMM 860 VIDEO MODULATOR SYSTEM 1
12 POSITION RACK MOUNT POWER SUPPLY
4 POSITION
RACK MOUNT
OR VMM 600/VMM 860 MODULAR
SINGLE-CHANNEL MODULATORS
POWER SUPPLY
The R.L. Drake VMM 600/VMM 860 Video
Modulator System is a professional quality modular headend system designed to optimize rack space. Up to 12 VMM 600 and/or
VMM 860 modulators can be racked alongside a single power supply in the Drake 12 position rack mount or up to 4 modulators can be racked in the 4 position rack mount. Either model is a high quality, fixed channel heterodyne audio/ video modulator.
The VMM 600 provides a modulated visual and
RF carrier output on any single VHF channel
2-13; Lowband channel A8; Midband channel
A-I and A5-A1; Superband channel J-W;
Hyperband channel AA-ZZ and AAA-XXX
(CATV 63-86) or UHF channel 14-35.
Aeronautical channels are offset positive with a tolerance of ±5 kHz as required by FCC rules.
The VMM 860 provides a modulated visual and
RF carrier output on any single Hyperband channel 87-135 or UHF channel 36-69.
The heterodyne conversion system, in conjunction with the use of a SAW filter, insures optimum vestigial selectivity for adjacent channel headends.
The modulators are 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 modulators accept standard (sync negative) polarity video at a 0.7 to 2.5 Vp-p level. All level controls are located on the front panel for ease of operation. Output level of
+45 dBmV is typical and is adjustable from
+30 to +45 dBmV.
Field-defeatable audio pre-emphasis enables passing of BTSC encoded standard baseband stereo audio signals. The Drake model
MMTS20 stereo encoder may be used with the
VMM when stereo audio is required.
® is a registered trademark of the R.L. Drake Company
© Copyright 2005 R.L. Drake Company P/N: 3852631C-04-2005
2 FRONT PANEL DESCRIPTION REAR PANEL DESCRIPTION
F1 R1
F2 R2
R3
F3
+5V
+12V
GND
R4
F4
F5
F6
Figure 1 Figure 2
F1 - AUDIO Level Control
The setting of this screwdriver adjustment determines the peak aural carrier deviation.
Clockwise rotation increases the carrier deviation.
R1 - VIDEO INPUT Connector
This is the baseband video input to the IF circuits. This input accepts baseband input thru 4.2 MHz video at levels from 0.7 Vp-p to
1.5 Vp-p.
F2 - VIDEO Level Control
The setting of this screwdriver adjustment determines the video modulation level.
Clockwise rotation increases the modulation depth.
F3 - POWER Indicator
Lights when the unit is connected to the required source of DC power via the rear panel
DC INPUT connector.
R2 - AUDIO INPUT Connector
This is an unbalanced audio input to the IF circuits. This “RCA” (phono) connector input accepts baseband thru 15 kHz audio at a nominal level of 250 mV RMS (approximately
0 dBm). NOTE: An externally accessible test point jumper defeats the audio pre-emphasis for stereo capability.
R3 - DC INPUT Connector
This 3-pin connector (Male) accepts the appropriate mating DC power cable. Observe proper orientation and wiring.
F4 - A/V Ratio Control
This screwdriver adjustment varies the level of the aural carrier over a range from 12 to 19 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 and thus decreases the A/V ratio.
R4 - RF OUTPUT Connector
This is the modulator output.
INTERNAL JUMPER
F5 - "CH#" (Channel)
The modulator is factory aligned to the channel number indicated.
F6 - RF Output Level
This screwdriver adjustment permits decreasing the RF output level approximately
12 dB below its specified output level as the control is rotated counterclockwise. The maximum output level is set with the adjustment fully clockwise.
AUDIO PRE-EMPHASIS
(On) MONO
AUDIO PRE-EMPHASIS
(Off) STEREO w/MMTS20
INSTALLATION 3
CONNECTIONS AND CONTROLS
All connections to and from each modulator are made through the rear panel. Figure 3 illustrates an installation with 12 modulator units combined through a passive signal combiner.
Additional channels can be added by using additional VMM 600 or VMM 860 modulators and either multi-por t 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 maintain a ±1 dB variation of adjacent channel carriers.
AC POWER
CORD
AUDIO INPUTS
VIDEO INPUTS
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. Units should be spaced apart by at least one panel height wherever possible, and some air movement is advisable in enclosed rack cabinets.
Excessive heat will shorten component life and modulator performance will be degraded without proper cooling.
VMM 600's/VMM 860's
DC POWER
CABLE
RF COMBINER
SYSTEM OUT
Figure 3
®
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
