Comtech EF Data SMS-7000, Инструкция по установке и эксплуатации

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SMS-7000 Modem Protection Switch Theory of Operation
Rev. 3 4–5
4.1.5 Modem Interfaces
Connectors on the modem side of the DSU and IFU chassis provide direct pin-for-pin
data connections to the applicable Comtech EFData modems.
A connector on the rear of the SCU provides remote and switch control of the modems
associated with the switch. Table 4-3 lists the SCU rear panel connector information.
Table 4-3. SCU Rear Panel Connectors
Connector Function Type Unit
J1 to J10 Data 50-pin D DSU
CP17 to CP36 RX and TX signals BNC IFU
J2 Modem remote 9-pin D SCU
The signal pin assignments of each channel depend on the configuration of the attached
prime modem. When commanded to load, the switch queries each prime modem for its
data configuration. It then configures the breakout panels of each DSM accordingly. The
breakout panels then switch the appropriate terrestrial data signals to the modem data
connectors.
When placed online, the backup connectors (J9 and J10) reflect the connectors of the
prime that is offline. The IF TX and RX signals (CP17 through CP36) are the remaining
modem interface signals. These are located at the rear of the IF chassis and are
numerically associated with their respective prime or backup modems.