Cessna 152 - Page 197

PILOT'S OPERATING HANDBOOK
SUPPLEMENT
CESSNA
300
NAV/COM
(TYPE RT-385A)
3.
NAVIGATION
OPERATING
FREQUENCY
READOUT.
4. ID-VOX-T
SWITCH
-
With
VOR
or
LOC
station
selected,
in
ID
position,
station
identifier
signal
is
audible;
in
VOX
(Voice)
position,
identifier
signal
is
sup-
pressed;
in
T
(Momentary
On)
position,
the
VOR
navigational
self-test
function
is
selected.
5.
NAVIGATION
RECEIVER
FRACTIONAL
MEGAHERTZ
SELECTOR
-
Selects
Nav
frequenc;:y
in
.05-MHz
steps
between
.00
and
.95 MHz;
simultaneously
selects
paired
glide
slope
frequency
and
DME
channel.
6.
NAV
VOL
CONTROL
-
Adjusts
volume
of
navigation
receiver
audio.
7.
NAVIGATIONRECEIVERMEGAHERTZSELECTOR
-
SelectsNAVfrequency
in
1-MHz
steps
between
108
and
117 MHz;
simultaneously
selects
paired
glide
slope
frequency
and
DME
channel.
8.
COMMUNICATION
RECEIVER-TRANSMITTER
FRACTIONAL
MEGAHERTZ
SELECTOR
-
Depending
on
position
of
5-0
switch,
selects
COM
frequency
in
.05-
MHz
steps
between
.000
and
J:175
MHz.
The
5-0
switch
identifies
the
last
digit
as
either
5
or
0.
9.
SQUELCH
CONTROL
-
Used
to
adjust
signal
threshold
necessary
to
activate
COM
receiver
audio.
Clockwise
rotation
increases
background
noise
(decreases
squelch
action);
counterclockwise
rotation
decreases
background
noise.
10.
COMMUNICATION
RECEIVER-TRANSMITTER
MEGAHERTZ
SELECTOR
-
Selects
COM
frequency
in
1-MHz
steps
between
118
and
135 MHz.
11. COM
OFF-VOL
CONTROL
-
Combination
on/off
switch
and
volume
control;
turns
on
NAV
/COM
set
and
controls
volume
of
communications
receiver
audio.
12.
BC
LAMP
-
Amber
light
illuminates
when
an
autopilot's
back-course
(reverse
sense)
function
is
engaged;
indicates
course
deviation
pointer
is
reversed
on
selected
receiver
when
tuned
to
a
localizer
frequency.
13.
COURSE
INDEX
•
Indicates
selected
VOR
course.
14.
COURSE
DE.ViATION
POINTER
-
Indicates
·course
deviation
from
selected
omni
course
or
localizer
centerline.
15.
GLIDE
SLOPE
"GS"
FLAG
-
When
visible,
red
GS
flag
indicates
unreliable
glide
slope
signal
or
improperly
operating
equipment.
Flag
disappears
when
a
reliable
glide
slope
signal
is
being
received.
16.
GLIDE
SLOPE
DEVIATION
POINTER
-
Indicates
deviation
from
ILS
glide
slope.
17.
NAV/TO-FROM
INDICATOR
-
Operates
only
with
a
VOR
or
localizer
signal.
Red
NA
V
position
(Flag)
indicates
unusable
signal.
With
usable
VOR
signal,
indicates
whether
selected
course
is
TO
or
FROM
station.
With
usable
localizer
signal,
shows
TO.
Figure
1.
Cessna
300
Nav/Com
(Type
RT-385A),
Operating
Controls
and
Indicators
(Sheet
2
of
3)
1
July
1978
3