Cessna 172S Pilot Operating Handbook page 18

SECTION 9 - SUPPLEMENTS
SUPPLEMENT 1 - FAA APPROVED
9. COMM FREQUENCY SELECTOR KNOB (INNER) -- This
smaller knob is designed to change the indicated frequency in
steps of 50-kHz when it is pushed in, and in 25-kHz steps
when it is pulled out.
incremented in 25 kHz steps with the knob pushed in and
8.33 kHz with the knob pulled out.
10. COMM FREQUENCY SELECTOR KNOB (OUTER) - - The
outer, larger selector knob is used to change the MHz portion
of the frequency display. At either band-edge of the 118 - 136
MHz frequency spectrum, an offscale rotation will wrap the
display around to the other frequency band-edge (i.e., 136
MHz advances to 118 MHz).
11. CHANNEL BUTTON -- Pressing the CHAN button for 2 or
more seconds will cause the unit to enter the channel program
(PG) mode. Upon entering the channel program mode, the
channel number
programmed. The desired channel can be selected by turning
the comm kHz knob. The channel frequency can be entered
by pushing the comm transfer button which will cause the
standby frequency to flash. The comm frequency knobs are
then used to enter the desired frequency. If dashes (located
between 136 MHz and 118 MHz) are entered instead of a
frequency, the corresponding channel is skipped in channel
selection mode. Additional channels may be programmed by
pressing the COMM transfer button and using the same
procedure. The channel information is saved by pushing the
CHAN button which will also cause the unit to return to the
previous frequency entry mode.
The channel selection mode (CH) can then be entered by
momentarily pushing the CHAN button. The comm frequency
knobs can be used to select the desired channel. The unit will
automatically default to the previous mode if no channel is
selected within 2 seconds after entering the channel selection
mode. The unit is placed in the transmit mode by depressing
a mic button.
Figure 1. Bendix/King KX 155A VHF NAVICOMM with KI 208 or KI
209A Indicator Head (Sheet 6 of 7)
81-10
For 8.33 kHz versions, channels are
will flash indicating
CESSNA
MODEL 172S
that it can be
Jul 8/98