TM 11-7440-232-12/NAVELEX 0967-LP-275-5010
RF OSCILLATOR
The stable 4.8 MHz crystal clock RF oscillator
(PIN 190-47861-01 for Code AB shelf) plugs into a
subassembly mounted in position A9 on the modem
shelf.
Position A9 is equipped with a front retainer
plate and a bracket which mounts the oscillator output
test jack and a ground test jack. The retainer plate
contains a center hole to allow adjustment of the
There are no operating controls on this
module.
Test pin-jacks are located on the front of the
module.
DATA CARRIER ALARM
The Data Carrier Alarm (PIN 090-46841-01)
PCC module plugs into the modem shelf. It provides
delayed alarm signals for transmit data, transmit carrier,
receive carrier, and receive data signals.
It provides individual alarm outputs if trouble
occurs in any of the monitored signal paths. The type of
alarm output used provides a fail-safe feature, in that,
failure of the circuit being monitored, failure of the alarm
circuit, or failure within the entire digital data modem will
always produce an alarm output.
The operating control (ALARM CUTOFF
switch) and the test pin-jacks are located at the front of
the PCC module.
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