Both coaxial relay based switch designs take their commands from the main modem or encoder alarm output, and switch if this fails.  RF detection also activates the switch in the event of signal failure. The design also includes a fail-safe feature allowing the L-band signal to be maintained in the unlikely event of a switch power failure. 

The redundancy switches have two basic modes of operation:  auto and manual.  In auto mode, RF detection and the external alarm input (dry contact alarm input port (for example; for a modem output alarm)) control the switching.  In manual mode either the serial port, RJ45 Ethernet port or local control buttons can control the switch path.   Front panel push buttons are also provided to select the mode and to select manually the main or standby feeds. 

Model 23206 is designed primarily for Rx (receive) feeds and is connected to main and standby decoders or IRDs. In the event of the main IRD failure the switch automatically routes the signal to the standby unit. If the switch itself fails, then the failsafe position is to route the L-band signals to the main IRD.  

Model 23205 is designed primarily for Tx (transmit) feeds and is connected to a main and standby encoder. In the event of a main failure the switch automatically routes the signal to the standby unit. If the switch itself fails, then the failsafe position is to route the L-band signals to the standby encoder.  

Key Features include:

• L-band 850-2150MHz
• RF Detection - 50 dB dynamic range, between   -40 to + 10 dBm
• 1U Chassis in 19” rack
• Remote and manual mode
• Isolation 65dB and Return Loss 15dB

Function: The 2 RF inputs (MAIN and STANDBY) both have RF detection, with a 50 dB dynamic range, between   -40 to + 10 dBm.  The user sets the threshold within these ranges which triggers a switchover. The unused RF port is internally terminated.