Cessna 172S Pilot Operating Handbook page 81

CES S NA
MODEL 1 72S
1 0. FREQUEN CY TRANSFER BUTTON (FRQ) -- The FRQ
transfer button when pressed exchanges the active and
standby frequencies. The new frequency becomes active an d
the former active frequency goes into standby.
1 1 . BFa (Beat Frequency Oscillator) BUTTON -. The B FO button
selects the BFO mode when in the depressed position. (See
note under item 3).
1 2. ADF BUTTON -- The ADF button selects either the ANT mode
or the ADF mode. The ANT mode is selected with the ADF
button i n the out position . The ADF mode is selected with the
ADF button in the depressed position.
1 3. LUBBER LINE -- I ndicates relative or magnetic heading of the
aircraft. The heading must be manually i nput by the pilot with
the headi ng (HOG) knob.
1 4. COMPASS CARD -- Manually rotatable card that i ndicates
relative or magnetic heading of aircraft, as selected by H OG
knob.
1 5. BEARING POINTER -- Indicates relative or magnetic bearing
to station as selected by H OG knob. If the relative heading of
North (N) is man ually selected under the l u bber line by the
pilot, then the bearing pointer indicates the relative bearing to
the station.
u nder the lubber line by the pilot, then the bearing poi nter
i ndicates the magnetic bearing to the station.
1 6. H EADING KNOB ( H OG) -- Rotates card to set i n relative or
magnetic h eading of aircraft.
Figure 1 . KR 87 Automatic Direction Finder (ADF) (Sheet 4 of 4)
July 8/98
SUPPLEME NT 6 - FAA APPROVED
If the aircraft's magnetic headi ng is selected
SECTION 9 - SUPPLEMENTS
S6-7