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3 faults (j7), 4 tx if output (cp1) – Comtech EF Data SDM-100A User Manual

Page 33

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SDM-100A Satellite Modem

Installation

Rev. 0

2–7

2.4.3 Faults (J7)

The Fault connector on the modem is used to interface FORM-C contact closures for the
purpose of fault reporting. There are three FORM-C summary fault contacts:

• Modulator

• Demodulator

• Common

equipment


For further discussion on the monitored faults, refer to Chapter 3.

To obtain a system summary fault, connect all FORM-C contacts in parallel.

The fault interface is provided on a 9-pin female D connector. Screw locks are provided
for mechanical security on the mating connector.

Pin #

Name

Function

1

NO

Common Equipment is OK

2 COM
3

NC

Common Equipment is FAULTED

4

NO

Modulator is OK

5 COM
6

NC

Modulator is FAULTED

7

NO

Demodulator is OK

8 COM
9

NC

Demodulator is FAULTED

Note: A connection between the Common (COM) and Normally Open (NO) contacts
indicates no fault.

2.4.4 TX IF Output (CP1)

This is the transmit IF connector. The output impedance is 75

(50

optional), and the

output power level is -5 to -30 dBm, in 0.1 dB steps.

For normal operation, the output will be a QPSK modulated result of the DATA I/O
connector, between 50 and 180 MHz.