Digital Alert Systems R165A - Manual (Page 4)

4
General Instructions
Mounting:
The 3000R-165 requires a minimum of 1.75 vertical inches of space in a standard 19” wide
EIA equipment rack. Slide the unit into the rack frame and secure it, using the 3000R/22M
mounting hardware supplied with the unit.
Connections:
1. The Video (or IF/RF) switches are mechanical relays, and connections to them
are made through 75
Ω F connectors on the rear of the unit. Connect your
cable for the default signal to the NC (normally closed) connector. Connect
your cable for your alternate signal - which you will substitute for the default
signal - to the NO (normally open) connector. Connect the cable to your modulator
or other destination to the COM (common or output) connector.
These connectors will switch either video signals, or may alternately be used to
switch high frequency signals, such as IF or RF. The frequencies useable are
shown on the frequency response charts included.
Of course, both inputs must be the same type of signal.
It is also permissible to use some relay sets for baseband video and some
for high frequency, since all switch modules are isolated.
2. If the signals being switched are baseband video, with audio following, connect the
audio signals to screw terminals of the same switch group, ensuring that the left and
right channels for the default audio are connected to the L NC 1 and 2, and the
R NC 1 and 2, and the signals for the alternate signal are attached to the L NO
1 and 2 and the R NO 1 and 2 connectors. The L OUT 1 and 2 and the R OUT
1 and 2 are routed to the modulator or other destination of the audio signals.
3. If you are using the unit with a contact closure switcher, connect the switch
for each Relay Unit to the connector for Contact Closure as appropriate. Refer to the
rear panel connections.
4. Connect the +12 VDC lead (white) from the power supply to the +12v terminal on the rear
panel, and the black lead to the GND terminal. Plug the power supply into a 90 -
264VAC power outlet, and the unit is ready to function.
Operation
When the contact closure for the appropriate Relay Unit is closed, the output (Com)
connection is switched from the default input (NC) to the alternate input (NO).