Comtech EF Data RCS11 Redundant Modem Protection Switch

RCS11 1:1 Modem Redundancy Switch

The Comtech RCS11 1:1 Redundancy Switch provides simple backup redundancy protection for all configurations of DMD15, DMD20, DMD50 and DMD2050 SCPC modems and the DM240 / DD240 DVB series of Digital Video Modulators and Demodulators.  

The backup functions of the RCS11 may be performed automatically, manually or from Terminal Mode. Operating in the automatic mode, the RCS11 immediately places a non-faulted backup modem online in the event of a primary online modem failure. In the manual mode, the user may designate the selected online primary modem either from the interactive front panel or a remote terminal interface.

Switch Operation

Only one modem in the pair (the online unit) is permitted to transmit its IF carrier signal at any one instant. For total security, the offline modem mutes its TX carrier, and the switch provides further isolation by using an RF relay within the unit. Unlike some other 1:1 redundancy systems, which use a passive power combiner for this function (losing approximately 3.5 dB in output power level), the switch does not introduce any attenuation of output signal level. The switches support all interfaces that each modem supports, including, RS-232/422, G.703, ASI, Ethernet, OC-3 copper, etc. Operators do not have to configure the interface type – control signals from the modems perform the selection automatically.