Cessna 172R Operating Handbook page 348

SECTION 9
-
SUPPLEMENT
The Comm portion incorporates an automatic squelch.
override the automatic squelch, the Comm volume control knob is
pulled
out.
squelch. A "T" will be displayed during transmit and "R" during
valid signal reception.
The Nav portion uses the pull
control receive the Nav signal
to
knob out to hear the Ident signal plus voice.
ident signal and still hear Nav voice.
attenuate the
All controls for the Nav/Comm, except those for navigation
course
selection,
transmitter.
lighting and the instrument panel flood lighting system. Operation
and description of the audio selector panel used in conjunction with
this radio is shown and described in Supplement 3 in this section.
The unit has a stuck microphone
microphone is keyed continuously
33 seconds, the
the active Comm frequency flashes to alert the pilot
of the stuck
.
S1-4
SUPPLEMENTS
- FAA APPROVED
1
Push the knob back
are mounted on the
Control lighting is provided by NAV/COMM interior
transmitter
mic condition.
in
to reactivate the automatic
feature of the Nav volume
out
Pull the volume control
Ident.
front panel of the receiver-
NOTE
alert feature.
for greater than
stops transmitting
CESSNA
MODEL 172R
Push the knob in
If the
and
Dec 2/96
To
to