SLM-5650 Satellite Modem
Revision 2
Installation
MN/SLM5650.IOM
2–8
2.3.7 Alarms
Connector, (J8)
The alarm connector provides Form C contact closures for alarm reporting. The three Form C
summary fault contacts are Modulator, Demodulator Common Equipment.
The alarm connection is a 9-pin female D connector (J8) located on the rear panel of the modem.
Screw locks are provided for mechanical security on the mating connector.
Pin #
Signal Function
Name
8
Unit Alarm is faulted
NO
3
Unit Alarm is not faulted
NC
7
Unit Alarm common
COM
5
Rx Alarm is faulted
NO
9
Rx Alarm is not faulted
NC
4
Rx Alarm common
COM
2
Tx Alarm is faulted
NO
6
Tx Alarm is not faulted
NC
1
Tx Alarm common
COM
2.3.8 Auxiliary Connector, (J9)
The auxiliary connector provides TTL open collector faults for the modulator and demodulator. A
TTL input for external transmit carrier mute. An Analog demodulator Q and I constellation
monitor. A programmable DC voltage monitor for the demodulators AGC.
(9-Pin Connector)
The auxiliary connection is a 9-pin female D connector (J9) located on the rear
panel of the modem. Screw locks are provided for mechanical security on the mating connector.
Pin #
Signal Function
Name
1 Chassis
Ground
GND
2 Spare
3 Demod
Q
channel
Q
4
AGC Monitor test point
AGC
5
Tx TTL fault
TxFLT
6 Spare
7
Ext carrier off
EXT
8
Demod I channel
I
9
Rx TTL fault
RxFLT
