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2 connector pinouts, 3 specification – Comtech EF Data SDM-650B User Manual

Page 65

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SDM-650B Satellite Modem

Configuration

Rev. 5

3–23

3.2.3.2 Connector Pinouts

The DS-1 interface is provided on a 15-pin female D connector accessible from the
modem rear panel. Screw locks are provided for mechanical security of the mating
connector.

Signal Function

Name

Pin #

SEND DATA

SD-A
SD-B

1
9

RECEIVE DATA

RD-A
RD-B

3

11

MASTER CLOCK

MC-A
MC-B

7
8

MODULATOR FAULT

----

14

DEMODULATOR FAULT

----

15

GROUND GND

2,

4

3.2.3.3 Specification

Circuits Supported

SD, RD, MOD FAULT, DEMOD FAULT

Data Rate

1.544 Mbit/s

±

100 bit/s

Pulse Width (RD)

324,

±

50 ns

Line Code

AMI or B8ZS (selectable)

RD Amplitude

2.75,

±

0.25V pk into a 100

Ω termination

SD Amplitude

3,

±

1.5V pk into a 100

termination

Jitter Attenuation (SD)

Meets AT&T Publication 62411 specification

Modulator Fault

Open collector output
15V max
20 mA current sink
Fault is open circuit

Demodulator Fault

Open collector output
15V max
20 mA current sink
Fault is open circuit