background image

Specifications     5

60 dB minimum,
luminance weighted.

±35 nSec referenced to 0 nSec
L/C delay (complies with FCC
rules, 76.605).

± 4% (10 to 90% APL).

± 4 degrees (10 to 90% APL).

140 mV minimum. Manual gain
adjustment with front panel
control. Over-Modulation LED set
for 25 kHz peak deviation
indication.

10K Ohms, Unbalanced.

75 

µ

Sec. (internally defeatable).

20 Hz to 15 kHz, ± 1 dB,
referenced to 75 

µ

Sec

pre-emphasis curve.
(20 Hz-100 kHz if preemphasis
is defeated).

±5 kHz, 0

0

 C to +50

0

 C.

1.0% maximum.

 -60 dB minimum, referenced
to 25 kHz peak deviation.

+28 dBmV.

+28 dBmV.

 75 Ohms.

115 VAC ±10%, 60 Hz,
10 WATTS.

0

0

 C to +50

0

 C, ambient.

19" W x 1.75" H x 6.75" D.

5 Lbs. (2.25 Kg).

Video S/N:

L/C Delay:

Differential Gain:

Differential Phase:

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:

COMPOSITE IF

LOOP

Output Level (V carrier):

Input Level (V carrier):

Input/Output

Impedances:

                GENERAL

AC Power Input:

Operating Temperature

Range:

Size:

Weight:

*Consult factory for custom channels

RF

Frequency Range:

Channels Available:

Output Level:

Output Impedance:

A/V Ratio:

Frequency Stability:

Intercarrier Frequency:

FCC Frequency

Offsets:

Spurious Outputs:

Broadband Noise:

VIDEO

Input level for 87.5%:

Input Impedance:

Frequency Response:

54 - 348 MHz.

VHF 2-13,
Lowband 1 (A8)
Midband 14-22 (A-I) and
95-99 (A5-A1),
Superband 23-36 (J-W),
Hyperband 37-44 (AA-HH)
Factory tuned for single
channel. *

+45 dBmV minimum, (typically
adjustable from +35 to
+45 dBmV). Note: If an output
level of less than +35 dBmV is
required, add an attenuator of
the appropriate value to the
modulator output.(eg., add a
10 dB pad for +30 dBmV output).

75 Ohms, return loss of 12 dB.

Audio Carrier -20 to -12 dB
referenced to video carrier,
adjustable.

± 5 kHz (Visual Carrier).

4.5 MHz.

All aeronautical channels
offset positive with a tolerance
of ±5 kHz.

 -65 dBc minimum, measured
at -15 dB A/V ratio and with
modulator output level of
+45 dBmV.

-77 dBc, referenced to video
carrier.
(4 MHz BW @ ±12 MHz offset).
-95 dBc @ ±36 MHz 0ffset.

1 Vp-p +/-3 dB, manual gain
adjust with front panel control.
Over-Modulation LED set for
87.5% depth of modulation
indication.

75 Ohms, return loss of 18 dB
minimum.

20 Hz to 4.2 MHz, ±1.0 dB.

Summary of Contents for VM1550

Page 1: ...Instruction Manual is a registered trademark of the R L Drake Company Copyright 2002 R L Drake Company P N 3857400K 3 2002 Printed in U S A VM1550 Commercial Video Modulator For use in NTSC systems...

Page 2: ...be moved with care Quick stops excessive force and uneven surfaces may cause the product and cart combination to overturn The lightning flash with arrow head symbol within an equilateral triangle is i...

Page 3: ...is grounded so as to provide some protection against voltage surges and built up static charges Article 810 of the National Electrical Code ANSI NFPA 70 provides information with regard to proper grou...

Page 4: ...is designed to accept video and audio baseband signals from a satellite receiver TV camera video tape recorder TV modulator or similar equipment The heterodyne conversion system in conjunction with t...

Page 5: ...Size Weight Consult factory for custom channels RF Frequency Range Channels Available Output Level Output Impedance A V Ratio Frequency Stability Intercarrier Frequency FCC Frequency Offsets Spurious...

Page 6: ...onnected to a source of AC power F2 AUDIO LEVEL Control The setting of this screwdriver adjustment determines the peak aural carrier deviation Clockwise rotation increases the carrier deviation Set th...

Page 7: ...AC power line outlet this cable grounds the instrument cabinet Connect to a nominal 115 VAC 10 60 Hz source Do not defeat the safety purpose of the attached line cord plug R1 RF OUT This is the modula...

Page 8: ...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 c...

Page 9: ...J K L M N O P Q R S T U V W AA BB CC DD EE FF GG HH B A N D L O W M I D H I G H S U P E R H Y P E R Channel Designation CABLE TV CHANNELS Visual Carrier Frequency MHz 55 25 61 25 67 25 77 25 83 25 91...

Page 10: ...ENT COVER THAT EXPOSES POTENTIALLY LETHAL VOLTAGES IF THE EQUIPMENT IS POWERED FROM AN AC POWER SOURCE REFER SERVICING TO A QUALIFIED TECHNICIAN ONLY CAUTION Audio Flat 3 2 1 3 2 1 FIGURE 4 VM1550 IF...

Page 11: ...Warranty Notes 11...

Page 12: ...personal check or 4 You specify some other method of return When calling the technician can estimate the repair charges for you over the phone This is another good reason to call before sending a uni...

Page 13: ...repair anduseareimportanttoobtainproperperformancefromthisproduct Thereforecarefully read the Instruction Manual This warranty does not apply to any defect that R L DRAKE COMPANY determines is due to...

Page 14: ...R L DRAKE COMPANY 230 Industrial Drive Franklin Ohio 45005 U S A Customer Service and Parts Telephone 1 937 746 6990 Telefax 1 937 743 4576 World Wide Web Site http www rldrake com...

Reviews: