Comtech EF Data SMS-7000, Installation And Operation Manual

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SMS-7000 Modem Protection Switch Installation
Rev. 3 2–17
2.4.1.6 IFU Connections (CP17 through CP36)
Refer to Figure 2-5.
Option – Cable CA/0813-8 is offered by Comtech EFData. Each prime and backup
modem in the configuration has an RX and TX coaxial connection to the modem face of
the IFU chassis. The switch and modems should have compatible characteristic IF
impedances of either 75
Ω
or 50
Ω
. Miniature coax is recommended to facilitate
harnessing.
2.5 Configuration Setup
This procedure will apply to the SDM-300, and current versions of the SDM-6000 and
SDM-8000 modems.
Note: Communications shall be established between the switch controller and the
modems. No visual activity will occur, however, relays may click and fault lamps may
come on. Use UTILITY/MODEM CONTROL to take command of the operation.
2.5.1 Configure Rack Setup
Note: The EIA-485 bus on the ribbon cable will be frozen if any communications are set
to EIA-232.
1. Check each modem for the following:
a. Remote Baud Rate: 9.6 or 19.2 kbit/s
b. Ribbon Cable: EIA-485 (2- or 4-wire)
c.
Remote Address: Note
2. Check IF switch for the following:
a. Modem Remote Baud Rate: 9.6 or 19.2 kbit/s
b. Remote Address: Config the prime and backup modem to match.