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3 receive output connectors, j6/j7, bnc, female – Comtech EF Data SDM-2020 User Manual

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SDM-2020 Satellite Demodulator

Revision 4

ASI/RS-422Data Interface

MN/SDM2020D.IOM

9–6

Single-ended signals (MF and DF fault signals) are open collector where:

V

oh

=12V max. and V

ol

=0.5V max. @ I

ol

=8 ma.


A pull-up resistor, external to the equipment, is required.

The fault signals, MF and DF, operate as follows: A fault is indicated by an “OFF” (high)
and OK status is indicated by an “ON” (low).

Table 9-2. RS-422 Connector Pinout (Per EIA-530), J5

Pin #

Signal Function

Name

Type

Comment

1 530

Shield

Shield

Mod/Demod

2

Transmit Data (TD-A)

BA-A

I

Modulator

3

Receive Data (RD-A)

BB-A

O

Demodulator

4

Request To Send (RS-A)

CA-A

I

Modulator

5

Clear To Send (CS-A)

CB-A

O

Modulator

6

DCE Ready (DM-A)

CC-A

O

Demodulator

7 Signal

Ground

AB GND

8

Receive Line Signal Detect (RR-
A)

CF-A O Demodulator

9

Receive Timing (RT-B)

DD-B

O

Demodulator

10

Receive Line Signal Detect (RR-
B)

CF-B O Demodulator

11

Terminal Timing (TT-B)

DA-B

I

Modulator

12

Send Timing (ST-B)

DB-B

O

Modulator

13

Clear To Send (CS-B)

CB-B

O

Modulator

14

Transmit Data (TD-B)

BA-B

I

Modulator

15

Send Timing (ST-A)

DB-A

O

Modulator

16

Receive Data (RD-B)

BB-B

O

Demodulator

17

Receive Timing (RT-A)

DD-A

O

Demodulator

18

N/C

19

Request To Send (RS-B)

CA-B

I

Modulator

20 Not

Used

21

Demodulator Fault (DF)

DF

O

Demodulator

22

DCE Ready (DM-B)

CC-B

O

Demodulator

23 Not

Used

24

Terminal Timing (TT-A)

DA-A

I

Modulator

25

Modulator Fault (MF) MF

O

Modulator

9.1.3.3 Receive

Output

Connectors, J6/J7, BNC, Female

Duplicate signals exit both of these connectors on the demodulator to deliver receive data
to the terrestrial interface. J6 and J7 are both active at all times, and no selection is
required.