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Comtech EF Data SMS-758 User Manual

Page 92

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Theory of Operation

SMS-758 Modem Protection Switch

4–32

MN/SMS758 Rev. 3

Backward Alarm 1 In

BWI1

12

Backward Alarm 2 In

BWI2

13

Backward Alarm 3 In

BWI3

14

Backward Alarm 4 In

BWI4

15

ADPCM 1 Audio In

A1I-A
A1I-B

45
29

ADPCM 1 Audio Out

A1O-A
A1O-B

46
30

ADPCM 2 Audio In

A2I-A
A2I-B

47
31

ADPCM 2 Audio Out

A2O-A
A2O-B

48
32

Demod Fault Relay

DF-C
DF-NO

16
50

Modulator Fault

MF

49

Demodulator Fault

DF

33

Deferred Maintenance Alarm

DMA

17

Note: MF and DF inputs are only on the prime and backup modem interface connectors,
not on the terrestrial data connector.