8 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:
(2) 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) 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:
(1) 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.
®
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
® is a registered trademark of the R.L. Drake Company
© Copyright 2005 R.L. Drake Company P/N: 3852469B-05-2005
®
VMM860AG/VMM860AS VIDEO MODULATORS 1
12 POSITION RACK MOUNT POWER SUPPLY
MODULATOR MODULATOR MODULATOR MODULATOR MODULATOR MODULATOR MODULATOR MODULATOR MODULATOR
AUDIO AUDIO
VIDEO
AUDIO
VIDEO
AUDIO
VIDEO
AUDIO
VIDEO
AUDIO
VIDEO
AUDIO
VIDEO
AUDIO
VIDEO
AUDIO
VIDEO
#
CH
PWR
A / V
RF
#
CH
PWR
A / V
RF
#
CH
PWR
A / V
RF
#
CH
PWR
A / V
RF
#
CH
PWR
A / V
RF
#
CH
PWR
A / V
RF
#
CH
PWR
A / V
RF
#
CH
PWR
A / V
RF
#
CH
PWR
POWER
ERROR
AUDIO
A / V
VIDEO
RF
2 5
CATV
+100
CATV
BC
TV
A / V
RF
MODULATOR MODULATOR
AUDIO
VIDEO
AUDIO
VIDEO
#
CH
PWR
A / V
RF
#
CH
PWR
A / V
RF
4 POSITION
RACK MOUNT
OR VMM860AG, VMM860AS
and other compatible modular units
POWER SUPPLY
POWER SUPPLY
The VMM860AG and VMM860AS modulators are members 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 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 VMM860AS has all of the features and specifications of the VMM860AG plus the additional capability of BTSC stereo audio.
The heterodyne conversion system, in conjunction with the use of a SAW filter, ensures optimum vestigial selectivity for adjacent channel headends. A FCC predistortion SAW response is standard.
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 VMM860AS has both a left and right audio input to accomodate stereo sources.
All level controls are located on the front panel for ease of operation. Output level is +45 dBmV and is adjustable over a 10 dB range.
On the VMM860AG, an audio pre-emphasis defeat, rear panel switch allows transmission of
BTSC encoded baseband stereo audio signals when used with the external Drake MMTS20 stereo encoder. A stereo encoder is built into the VMM860AS model.
2 FRONT PANEL CONTROLS and INDICATORS
F5
F6
F7
F1
F2
F3
F4
VMM860AG
POWER/
ERROR
AUDIO
VIDEO
2 5
CATV
+100
C A T V
B C
T V
A / V
R F
VMM860AG VMM860AS
PWR
A
V
VMM860AS
P.LK
CATV
+100
2 5
C A T V
B C T V
A / V
R F
F8
F9
F10
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 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. Clockwise rotation increases the carrier deviation.
F3 - VIDEO Level Control
The setting of this screwdriver adjustment determines the video modulation level. CW rotation increases the modulation depth.
Figure 1
Setting for CATV
channel "125"-
2 5
Setting for CATV
channel "25"-
2 5
CATV
+100
CATV
BC
TV
CATV
+100
CATV
BC
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. Typically, the aural carrier should be adjusted to approximately 15 dB below the visual carrier. Clockwise rotation increases the aural carrier level.
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.
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. Here are two examples:
F7 - RF Output Level
This screwdriver adjustment permits adjustment of the RF output level over a minimum of 10 dB range. Maximum output is at full CW.
F8 - P. LK (Pilot Lock)
This LED indicates that the BTSC circuitry in the VMM860AS has locked to the video sync reference.
F9 - Audio Overmodulation
This LED illuminates when the audio input level reaches full modulation. Set F2 for just an occasional flicker. (VMM860AS)
F10 - Video Overmodulation
This LED illuminates at 87.5% video modulation. Advance F3 CW until F10 just lights then back off until F10 just goes out. (VMM860AS)
SPECIFICATIONS 7
RF
Frequency Range:
FCC Frequency Offsets:
Output level:
Output Impedance:
A/V Ratio:
Frequency Stability:
Output Flatness:
Output Amplitude Stability:
Intercarrier Frequency:
Spurious Outputs (5 to 900 MHz):
In-Channel C/N:
Broadband Noise:
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).
+45 dBmV minimum (10 dB adjustment range).
75 Ohms, 8 dB return loss.
Audio carrier level, adjustable from -22 to -12 dB referenced to video carrier level.
Within ±5 kHz
From 54 to 864 MHz, less than 3 dB change.
±1 dB
4.5 MHz
-60 dBc, (-15 dB A/V ratio and output level of +45 dBmV).
65 dB typical, 4 MHz bandwidth.
-78 dBc typicial, 4 MHz bandwidth @ +45 dBmV output.
VIDEO
Input Level for 87.5% Modulation:
Video Over-modulation LED:
Input Impedance:
Frequency Response:
C/L Delay:
Differential Gain:
Differential Phase:
0.65 Vp-p to 1.5 Vp-p. Gain adjust with front panel control.
Trips at 87.5 % depth of modulation. (VMM860AS only)
75 Ohms, return loss of 26 dB minimum.
20 Hz to 4.2 MHz, ±1 dB.
Within 50 nSec. of FCC predistortion.
3% maximum (10 to 90% APL).
3 0 maximum (10 to 90% APL).
AUDIO, VMM860AG
Input Level for +/- 25 kHz Deviation:
Input Impedance:
Pre-emphasis:
Frequency Response:
S/N ratio:
Total Harmonic Distortion:
125 mV rms to 2.5 V rms. Manual gain adjust with front panel control.
Greater than 10 K Ohms, unbalanced.
75
µ
Sec. normal, defeatable (flat) by rear panel switch for
BTSC baseband stereo compatibility.
40 Hz to 15 kHz, ±1.0 dB referenced to 75
µ
Sec.
pre-emphasis curve.
40 Hz to 100 kHz, ±0.5 dB if pre-emphasis is defeated.
65 dB.
Less than 0.5 %.
AUDIO, VMM860AS
Input Level:
Over Modulation Indicator:
Input Impedance:
Channel Separation:
Frequency Response:
S/N Ratio:
THD:
250 mV to 2.5 V rms for 25 kHz L+R deviation.
Trips at ±25 kHz L+R deviation.
Greater than 10 K Ohms, unbalanced.
> 30 dB from 100 Hz to 10 kHz.
> 25 dB from 10 kHz to 14 kHz.
±1 dB of 75
µ
Sec pre-emphasis curve, 50 Hz to 14 kHz.
> 60 dB
Less than 0.5 %
GENERAL
DC Power Input:
Operating Temperature:
Size:
Weight:
+12 V ±5% at 200 mA (AG) or 220 mA (AS).
+5 V ±5% at 350 mA (AG) or 400 mA (AS).
0 0 C to +50 0 C ambient.
1” W x 3.5” H x 7.5” D (AG) or 8" D (AS)
12 oz. (AG) or 13.5 oz. (AS)
Specifications subject to change without notice or obligation.
6 BROADCAST TV CHANNEL OUTPUT FREQUENCIES
TABLE 2: BC TV CATV
+100
CATV
BC
TV
CATV
+100
CATV
BC
TV
Channel Number
Visual Carrier
Frequency (MHz)
8
9
10
11
12
13
5
6
7
2
3
4
55.25
61.25
67.25
77.25
83.25
175.25
181.25
187.25
193.25
199.25
205.25
211.25
Channel Number
Visual Carrier
Frequency (MHz)
645.25
651.25
657.25
663.25
669.25
675.25
681.25
687.25
693.25
699.25
585.25
591.25
597.25
603.25
609.25
615.25
621.25
627.25
633.25
639.25
525.25
531.25
537.25
543.25
549.25
555.25
561.25
567.25
573.25
579.25
471.25
477.25
483.24
489.25
495.25
501.25
507.25
513.25
519.25
705.25
711.25
717.25
723.25
729.25
735.25
741.25
747.25
753.25
759.25
765.25
771.25
777.25
783.25
789.25
795.25
801.25
45
46
47
48
49
40
41
42
43
44
35
36
37
38
39
30
31
32
33
34
25
26
27
28
29
20
21
22
23
24
14
15
16
17
18
19
65
66
67
68
69
60
61
62
63
64
55
56
57
58
59
50
51
52
53
54
REAR PANEL CONNECTIONS / INTERNAL JUMPERS 3
R1 R1
R2
R3
VIDEO INPUT
AUDIO INPUT
+5V
+12V
GND
DC INPUT
FLAT
NORM
R5 R2
R6
VIDEO INPUT
AUDIO L
PWR
+ 5 V
+ 1 2 V
G N D
AUDIO R
RF OUT
R3
R4 R4
RF OUT
VMM860AG
R1 - VIDEO INPUT
This is the nominal 1 Vp-p baseband video input to the modulator.
R2 - LEFT/MONO AUDIO INPUT
This is an unbalanced audio input to the modulator circuits. This “RCA” (phono) connector input accepts mono audio in the case of the VMM860AG or the left channel audio input in the case of the VMM860AS.
R3 - DC INPUT Connector
This 3-pin connector (Male) accepts the appropriate mating DC power cable.
VMM860AS
Figure 2
R4 - RF OUTPUT
This is the modulator output.
R5 - AUDIO PRE-EMPHASIS SWITCH
VMM860AG only. This switch allows selection of either normal audio pre-emphasis or flat audio response. For normal mono audio, 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.
R6 - RIGHT AUDIO INPUT
VMM860AS only. This is the an unbalanced input for the right channel stereo audio.
INTERNAL JUMPER SETTING: STD, HRC, IRC
STD Drawing is not to scale. AG and AS
models differ. The correct set of pins
HRC is located directly next to the 45.75
MHz crystal. No jumper installed gives
IRC STD setting.
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 VIDEO INPUTS maintain a ±1 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 performance will be degraded without proper cooling.
MODULATOR UNITS
(Fixed channel and/or Agile types)
DC POWER
CABLE
RF COMBINER
SYSTEM OUT
POWER SUPPLY REQUIREMENT
Power for modulators mounted in the RMM12 rack mounting cage is to be supplied by a
Drake model PSM121 power supply. Up to 12 modulators may be powered.
The power supply in the four position rack system can power up to four VMM860AG or
VMM860AS modulators or any mix of fixed and agile VMM models up to four total modulators.
Figure 4
FREQUENCY CHART
The chart on the following page shows the standard CATV channel coverage for these agile models. 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.
TABLE 1: CATV CATV
+100
CATV
BC
TV
CATV CHANNEL OUTPUT FREQUENCIES 5
CATV
+100
CATV
BC
TV
Output Channel
Switch Setting
51
52
53
54
47
48
49
50
43
44
45
46
39
40
41
42
35
36
37
38
31
32
33
34
25
26
27
28
29
30
63
64
65
66
67
68
69
59
60
61
62
55
56
57
58
19
20
21
22
23
24
13
14
15
16
17
18
07
08
09
10
11
12
02
03
04
05
06
Visual Carrier
Frequency (MHz)
Frequency
Offset (kHz)
307.25
313.25
319.25
325.25
331.25
337.25
343.25
349.25
355.25
361.25
367.25
373.25
235.25
241.25
247.25
253.25
259.25
265.25
271.25
277.25
283.25
289.25
295.25
301.25
121.25
127.25
133.25
139.25
145.25
151.25
157.25
163.25
169.25
217.25
223.25
229.25
55.25
61.25
67.25
77.25
83.25
175.25
181.25
187.25
193.25
199.25
205.25
211.25
379.25
385.25
391.25
397.25
403.25
409.25
415.25
421.25
427.25
433.25
439.25
445.25
451.25
457.25
463.25
469.25
475.25
481.25
487.25
493.25
+12.5
+12.5
+12.5
+12.5
+25
+12.5
+12.5
+12.5
+12.5
+12.5
+12.5
+12.5
+12.5
+12.5
+12.5
+12.5
+12.5
+12.5
+12.5
+12.5
+12.5
+12.5
+12.5
+12.5
±12.5
±12.5
±12.5
NONE
NONE
NONE
NONE
NONE
NONE
NONE
+12.5
+12.5
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
+12.5
+12.5
+12.5
+12.5
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
121
122
123
124
125
126
115
116
117
118
119
120
109
110
111
112
113
114
100
101
102
103
104
105
106
107
108
127
128
129
130
131
132
133
134
135
Output Channel
Switch Setting
Visual Carrier
Frequency (MHz)
88
89
90
91
92
93
82
83
84
85
86
87
94
95
96
97
98
99
76
77
78
79
80
81
70
71
72
73
74
75
571.25
577.25
583.25
589.25
595.25
601.25
607.25
613.25
619.25
625.25
631.25
637.25
499.25
505.25
511.25
517.25
523.25
529.25
535.25
541.25
547.25
553.25
559.25
565.25
643.25
91.25
97.25
103.25
109.25
115.25
CATV +100
739.25
745.25
751.25
757.25
763.25
769.25
775.25
781.25
787.25
793.25
799.25
805.25
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
811.25
817.25
823.25
829.25
835.25
841.25
847.25
853.25
859.25
CATV
+100
CATV
Frequency
Offset (kHz)
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
+25
+25
BC
TV
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
NONE
