Comtech EF Data SMS-758 - Manual (Page 110)

Theory of Operation SMS-758 Modem Protection Switch
4–50 MN/SMS758 Rev. 3
4.10 Online Telemetry
The online telemetry (Figure 4-22) is a 10.5” x 3.5” module that fits in slot 6 of the upper
front section of the switch chassis. It reports the online status of each prime modulator
and demodulator. Refer to Figure 4-23 for a block diagram of the online telemetry
module.
4.10.1 Specifications
Number of Channels 8 modulator and 8 demodulator.
Switching Format Form C contacts.
4.10.2 Theory of Operation
The M&C controls the online telemetry module through the address decoder/driver with
an 8-bit data bus and 2 device select lines. Sixteen SPDT relays (Form C) can be
switched to indicate the online status of eight prime modulators and eight prime
demodulators.