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 intended to alert the user to the
presence of uninsulated "dangerous voltage" within
the product's enclosure that may be of sufficient
magnitude to constitute a risk of electric shock to
persons.
The exclamation point within an equilateral triangle is
intended to alert the user to the presence of important
operating and maintenance (servicing) instructions in
the literature accompanying the product.
WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE THIS PRODUCT TO
RAIN OR MOISTURE.
A product and cart combination should be moved
DO NOT OPEN THE CABINET, REF
ER SERVICING TO QUALIFIED PERSONNEL ONLY.
CAUTION: TO PREVENT ELECTRIC SHOCK, DO NOT USE THIS (POLARIZED) PLUG WITH AN EXTENSION
CORD RECEPTACLE OR OTHER OUTLET UNLESS THE BLADES CAN BE FULLY INSERTED TO
PREVENT BLADE EXPOSURE.
ATTENTION: POUR PREVENIR LES CHOCS ELECTRIQUES, NE PAS UTILISER CETTE FICHE POLARISEE
AVEC UN PROLONGATEUR, UNE PRISE DE COURANT OU UNE AUTRE SORTIE DE COURANT,
SAUF SI LES LAMES PEUVENT ETRE INSEREES A FOND SANS EN LAISSER AUCUNE PARTIE A
DECOUVERT.
Important Safety Instructions:
1.Read Instructions: All the safety and operating instructions should be read before the product is operated.
2. Retain Instructions: The safety and operating instructions should be retained for future reference.
3. Heed Warnings: All warnings on the product and in the operating instructions should be adhered to.
4. Follow Instructions: All operating and use instructions should be followed.
5. Cleaning: Unplug this product from the wall outlet before cleaning. Do not use liquid cleaner
6. Attachments: Do not use attachments that are not recommended by the product manufacturer as they may cause hazards.
7. Water and Moisture: Do not use this product near water—for example, near a bathtub, wash bowl, kitchen sink or laundry tub; in a wet basement;
or near a swimming pool; and the like.
8. Accessories: Do not place this product on an unstable cart, stand, tripod, bracket, or table. The product may fall, causing serious injury to a child
or adult, and serious damage to the product. Use only with a cart, stand, tripod, bracket, or table recommended by the manufact
the product. Any mountin
manufacturer.
9. A product and cart combination should be moved with care. Quick stops, excessive force, and uneven surfaces may cause the product and cart
combination to overturn.
10. Ventilation: Slots and openings in the cabinet are provided for ventilation and to ensure reliable operation of the product and to protect it from
overheating, and these openings must not be blocked or covered. The openings should never be blocked by placing the product on a be
or similar surface. This product should not be placed in a built-in installation such as bookcase or rack unless proper ventilation is provided or the
manufacturer's instructions have been adhered to.
11. Power Sources: This product should be operated only from the type of power source indicated on the marking label. If you are not sure of the type
of power supplied to your home, consult your product dealer or local power company. For products intended to operate from battery power, or other
sources, refer to the operatin
12. Grounding or Polarization: This product may be equipped with a polarized alternating-current line plug (a plug having one blade wider than the
other). This plug will fit into the power outlet only one way. This is a safety feature. If you are unable to insert the plug fully into the outlet, try reversing
the plug. If the plug should still fail to fit, contact your electrician to replace your obsolete outlet. Do not defeat the saf
plug. Alternate Warnings – If this product is equipped with a three-wire grounding- type plug, a plug having a third (grounding) pin, the plug will only fit
into a grounding-type power outlet. This is a safety feature. If you are unable to insert the plug into the outlet, contact your electrician to replace your
obsolete outlet. Do not defeat the safety purpose of the grounding-type plug.
g of the product should follow the manufacturer's instructions, and should use a mounting accessory recommended by the
g instructions.
s or aerosol cleansers. Use a damp cloth for cleaning.
d, sofa, rug,
ety purpose of the polarized
Cautions Statements continued
13.
Outdoor Antenna Grounding: If an outside antenna or cable system is connected to the product, be sure the antenna or cable system 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 grounding of the mast and supporting structure, grounding of the lead-in wire to an
antenna discharge unit, size of grounding conductors, location of antenna-discharge unit, connection to grounding electrodes, and requirements for
the grounding electrode.
14. Power-Cord Protection: Power-supply cords should be routed so that they are not likely to be walked on or pinched by items placed upon or against
them, paying particular attention to cords at plugs, convenience receptacles, and the point where they exit from the product.
15. Lightning: For added protection for this product during a lightning storm, or when it is left unattended and unused for long periods of time, unplug it
from the wall outlet and disconnect the antenna or cable system. This will prevent damage to the product due to lightning and power-line surges.
16. Power Lines: An outside antenna system should not be located in the vicinity of overhead power lines, other electric light or power circuits, where it
can fall into such power lines or circuits. When installing an outside antenna system, extreme care should be taken to keep from touching such power
lines or circuits as contact with them may be fatal.
17. Overloading: Do not overload wall outlets, extension cords, or integral convenience receptacles as this can result in a risk of fire or electric shock.
18. Object and Liquid Entry: Never push objects of any kind into this product through openings as they may touch dangerous voltage points or short-out
parts that could result in a fire or electric shock. Never spill liquid of any kind on the product.
19. Servicing: Do not attempt to service this product yourself as opening or removing covers may expose you to dangerous voltage or other hazards.
Refer all servicing to qualified service personne
20. Damage Requiring Service: Unplug this product from the wall outlet and refer servicing to qualified service personnel under the following conditions:
a) When the power-supply cord or plug is damaged,
b) If liquid has been spilled, or objects have fallen into the product,
c) If the product has been exposed to rain or water,
d) If the product does not operate normally by following the operating instructions.
Adjust only those controls that are covered by the operating instructions as an improper adjustment of other controls may result in damage and will
often require extensive work by a qualified technician to restore the product to its normal operation, e. If the product has been dropped or damaged
in any way, and f. When the product exhibits a distinct change in performance—this indicates a need for service.
21. Replacement Parts: When replacement parts are required, be sure the service technician has used replacement parts specified by the manufacturer
or have the same characteristics as the original part. Unauthorized substitutes may result in fire, electric shock or other hazards.
22. Safety Check: Upon completion of any service or repairs to this product, ask the service technician to perform safety checks to determine that the
product is in proper operating condition.
23. Wall or Ceiling Mounting: The product should be mounted to a wall or ceiling only as recommended by the manufacturer.
24. Heat: The product should be situated away from heat sources such as radiators, heat registers, stoves, or other products (including amplifiers) that
produce heat.
l.
3
4 T
able of Contents / Description / Specifications
TABLE OF CONTENTS
2Caution Statements
2Important Safety Instructions
4Table of Contents / Description / Specifications
5Front/Rear Panel Controls and Indicators
6Operation
7Adjustments
8
Channel Assignments
10
Service / If You Need To Call For Help
11
Warranty
VM SERIES VIDEO MODULATOR
DESCRIPTION
The R.L Drake VM2860 and VM2862 Video Modulators are high
quality, vestigial sideband units with synthesized visual and aural
carriers. They are designed to accept NTSC video and audio
baseband signals from a satellite receiver or similar equipment.
Front panel video and audio level controls with accompanying
modulation indicators permit easy setup of the proper modulation
levels. The A/V ratio and RF output level controls are also provided
on the front panel. A rear panel EAS alternate IF input is also
provided. The VM2860 model is for applications with mono audio
and the VM2862 model provides BTSC stereo encoded audio.
Synthesized operation provides complete frequency agility, allowing
front panel selection of any standard CATV channel from 2 to 135
(54 to 862 MHz band). FCC required offsets for aeronautical
channels are automatically provided for each channel that requires
an offset. For special applications, IRC or HRC CATV frequencies
or off-air broadcast frequencies can be selected from the front panel.
A high quality IF SAW filter with FCC predistortion eliminates
adjacent channel interference and provides optimum delay
characteristics.
SPECIFICATIONS - VM2860 / VM2862
VIDEO INPUT
Connector: “F” Female
Impedance: 75 ohms
Video Input Level: 0.7 volt Peak-to-Peak
Signal-to-Noise Ratio: 58 dB
Differential Gain: 2.0%
Differental Phase: 1.0 degree
Over-modulation Indicator: 87 to 92%
Channel Modes: CATV (STD,IRC,HRC) UHF, VHF
Power Level Range: +50 to +60 dBmV
Video Flatness: fv-0.5 to fv+4.2 MHz : 1.5 dB p/v
Carrier-to-Noise: -63 dB
Broadband Noise: -77 dBc
Spurious Outputs: -63 dBc
Aural/Visual Carrier Ratio: -15 ± 5 dB
Return Loss: 18 dB
L/C Delay: Per FCC Requirements
RF OUTPUT
Connector: “F” Female
Impedance: 75 ohms
Return Loss: 12 dB
GENERAL
AC Power:
Temperature Range:
Fuse: Fuse: 0.4A Type T 250 V
Size: 19.0 x 14.25 x 1.75 in
Weight:
117 VAC ± 10%, 60 Hz,
29 Watts max
32° to 122° F
7 lbs.
A manual or auto-switching alternate IF input, labeled EAS input,
is provided for connection of an Emergency Alert System 44 MHz
IF signal. When the EAS IF signal appears at the EAS input, the
main video and audio modulated IF is replaced by the EAS input
signal.
The EAS/Alternate IF feature allows a choice between manual
and automatic selection of the EAS/ALT IF input signal. This
is done through a 3 position terminal strip on the rear of the unit.
In the manual mode the EAS/ALT IF feature is activated by a contact
closure switch, which completes a ground connection. In the
automatic mode, two positions on the terminal strip are jumpered
together enabling an automatic detection circuit in the unit. When an
EAS/ALT IF signal is routed to the EAS/ALT port the unit automatically
switches to that alternate signal.
MONO AUDIO (VM2860)
Input Impedance: Greater than 10k ohms, unbalanced.
Frequency Range: 50 Hz to 15 kHz
Frequency Response: ± 0.5 dB