Radyne RCS20, Инструкция по установке и эксплуатации

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Operation RCS20 M:N Redundancy Switch
3-2 TM056 - Rev. 2.3
3.4 IFS20 Major Assemblies
The IFS20 IF Switch interfaces the IF signals of the Modems with the earth station IF system and
provides back-up switching. The unit provides all of the switching relays, signal combiners and
splitters, terminations and interconnecting cables that are necessary to connect any combination of
up to eight Modulators and Demodulators to eight independent uplink and eight independent
downlink Transponders.
The IFS20 has no internal power supply. It receives its DC power from the RCU20 through the cable
that connects to J35. The IFS20 internal connectors are SMB-type.
The major parts of the IFS20 are:
1. Eight uplink and eight downlink IF Relays.
2. Back Panel.
3.5 IF Switch Relays
The IFS20 contains 16 IF Switch Relays; eight uplink and eight downlink. The relays switch the IF
signals to the Backup units. The signals to each downlink relay pass through a splitter with a loss
of about 3.5 dB (including the loss due to energy splitting).
3.6 DDS20 Major Assemblies
The DDS20 Data Switch provides terrestrial interface and data signal switching for up to nine
independent pairs of Modulators and Demodulators. There are two parallel and independent backup
busses allowing any of the eight on-line Modulators and Demodulators to be switched to either of
the backup Modulators or Demodulators. The major components of the DDS20 listed in Table 3-1.
Table 3-1. DDS20 Major Components
Motherboard Contains the modem connectors and backup busses.
Slide-In Data Switch
Interface Modules
One for each prime modem, containing terrestrial interface
connectors and data switch relays.
Housing Contains the card guides and mounting ears for the motherboard.
Rear Panel Contains the electrical connections.
The DDS20 has no internal power supply, it receives DC power from the RCU20 through the cable
that connects at J31.