RCU operation is identical to radio operation with a few exceptions. You may: Load
or offset SC frequencies, receive or send an ERF, change modes or functions,
change channels, select COMSEC keys, select
or CT operation, select data
rates, and clear FH data in the radio, The RCU operation is slower than radio opera-
tion. You must wait for for radio signal to reach RCU to continue operation. Other-
wise, some keyboard entries, etc. wont be accepted. Carefully read the following
notes, determine what procedure you wish to perform: then refer to radio operating
procedures in Chapter 2.
The radio and battery warnings and cautions at the front of this
manual also apply to the RCU. Read them carefully.
Make sure to perform scheduled PMCS and routine checks as re-
Set radio FCTN switch to REM AFTER turning on RCU. Data will
be lost if radio FCTN is set to REM before RCU is turned on. Use
the radio to clear COMSEC keys that are loaded in the radio. If two-
wire is cut, disconnected, or radio FCTN switch is not set to REM,
RCU display shows "OPEN . Radio battery life condition must be
set at the radio. RCU battery life condition is set at the RCU. RCU
data rates are set at the RCU.
When RCU FCTN is set to
, the companion radio also goes
to STBY after about 16 seconds. Likewise, if the two-wire is cut
or disconnected, the companion radio will go into
Local fill of SC and FH data must be done with the radio. ERF may
be received using the RCU.
It is not possible to clear COMSEC keys from radio at RCU.
Set RCU COMSEC switch to
when RCU FCTN switch is set to
If radio is being controlled by a CM, disconnect CM before using