Comtech EF Data SMS-7000 - Manual (Page 31)

SMS-7000 Modem Protection Switch Introduction
Rev. 3 1–11
1.2.3 IF Switch Unit (IFU)
All IF switching is performed in the IFU. In a typical application, the IFU is attached to
the DSU. If necessary, the unit can be mounted separately and interconnected with an
extended length interface cable. This procedure is recommended if mounting multiple
switches in the top of a rack or when separate mounting facilitates IF cabling.
The user has access to one downlink and one uplink port for each of the eight channels
(Figure 1-5).
Each prime and backup satellite modem in the configuration has an RX and TX coaxial
connection to the modem side of the DSU chassis (Figure 1-6).