Comtech EF Data CRS-120 - Manual (Page 19)

1:1 Redundancy Switch Revision 3
Introduction MN/CRS120.IOM
1–5
1.3 Front Panel
The CRS-120 Switch: On the front panel (Figure 1-3) of the unit are the following IF connectors,
which are BNC female:
J3 Tx IF Mon 20dB, a sample of the Tx Online signal for test purposes
J4 Tx IF Online, the output connector with the Tx Carrier
J5 Tx IF Standby, which connects to the Standby modulator
The CRS-120L Switch: On the front panel (Figure 1-4) of the unit are the following connectors,
which are SMA female:
J3 20dB Mon, a sample of the Online signal for test purposes
J4 Online, the output connector with the Tx Carrier
J5 Standby, which connects to the Standby modulator
Additionally, on the front panel are two LEDs, marked ‘A Online’ and ‘B Online’. Only one of
these LEDs will illuminated at any given time, and provide a visual indication of which of the
two units is presently carrying traffic. There also is a 9-pin D female connector (J2) with a set of
From-C contacts to indicate whether A or B is online.
Also on the front panel is a ground stud, which may be used, if desired, to bond the chassis of the
unit to the system ground. The front panel also contains mounting points to attach an optional 19-
inch panel to secure the unit to rear of a cabinet if desired.
The front panel also contains DIP to select the whether a carrier is produced in an unfaulted
Standby unit.
1.4 Rear Panel
Located on the rear panel are the two Alarm Interface connectors for the ‘A’ and ‘B’ units, each
being 15-pin ‘D’ type female. These are connected to the Modulators using the two supplied
cables.
IMPORTANT
REMEMBER!
The top unit is ‘A’
The bottom unit is ‘B’
The CRS-120L Switch: The CRS-120L (L-Band) has two connectors (J6A/J6B) ‘A’ and ‘B’,
which are both SMA female. Connection is made to the pair of Modulators using coaxial cables
with SMA-Male connectors.