Comtech EF Data CRS-311 - Manual (Page 38)

CRS-311 1:1 Redundancy Switch Revision 7
Introduction MN/CRS311.IOM
1–14
1.3.6 CRS-281x IF Switch Modules
Each CRS‐281/281x IF Switch Module connects the Tx IF signal on the Up Converter to the
appropriate online modulator, and passively splits the Rx IF signal to provide both demodulators
with the same IF signal from the LNB, thus reducing switching time.
Additionally, the CRS‐281A IF Switch Module switches all of the BUC and LNB interface signals
that are multiplexed onto the Tx and Rx coaxial cables:
• Tx and Rx L‐Band signals • 10 MHz reference to BUC and LNB
• DC Power to BUC and LNB • FSK signaling to the BUC
1.3.6.1 CRS-281x IF Switch Modules for the CDM-Qx/QxL
1.3.6.2 CRS-281x IF Switch Modules for the SLM-5650/5650A
Figure 1-19. CRS-281 IF Switch Module:
70/140 MHz Type ‘BNC’ (PL/12040-3 [75 Ω]
or PL/12040-4 [50 Ω])
Figure 1-20. CRS-281A IF Switch Module:
L-Band Type ‘N’ 50 Ω (PL/13017-1)
Figure 1-21. CRS-281 IF Switch Module:
Type ‘TNC’ 50 Ω (PL/12040-2)
Figure 1-22. CRS-281L IF Switch Module:
L-Band Type ‘N’ 50 Ω (PL/12040-1)