Comtech EF Data CRS-120 - Manual (Page 15)

1–1
Chapter 1. INTRODUCTION
1.1 Introduction
The 1:1 Redundancy Switch (Figure 1) is available in either a 70/140 MHz application or an
L-Band application to support modulator backup.
• The CRS-120 is a companion product that provides 70/140 MHz switching (75Ω only)
for the Comtech EF Data (CEFD) CDM-710 Satellite Modem equipt as a Modulator and
is procurable as 1:1 Switch Kit P/N KT/11084-3 consisting of the switch and the
necessary installation cables.
• The CRS-120L is an L-Band version of the 1:1 Switch for operation with the
L-Band version of the . A 1:1 Switch Kit, KT/ 11362-3 is available for L-Band.
The 1:1 controller is within the modulator and provides control and drive signals to the 1:1
redundancy switch. This combination continuously monitors a pair of modulators so that, in the
event of an equipment failure (or an undesired traffic condition), the subsystem automatically
switches IF signals from the failed unit to the Standby unit. In this manner, IF traffic paths are
fully protected. The CRS-120 / CRS-120L provides IF / L-Band switchover only. It does not
support switchover of data circuits.
CRS-120 CRS-120L
Figure 1-1. 1:1 Redundancy Switch