Cessna TURBO CENTURION T210M 1978 Pilot Operating Handbook page 285

PILOT'S OPERATING HANDBOOK
SUPPLEMENT
CESSNA 400 ADF
(TYPE R-446A)
TO OPERATE AS AN AUTOMATIC DIRECTION FINDER:
1.
OFF/VOL Control -- ON.
2. PRI Frequency Selectors -- SELECT desired operating frequency.
3. SEC Frequency Selectors -- SELECT desired operating frequency.
4. 1-2 Selector Switch -- 1 position.
NOTE
1-2 selector switch can be placed in the 2 position for
operation on secondary frequency. The re-select lamp will
flash only when frequency selection is outside of operat-
ing range of the receiver.
5. ADF SPEAKER/PHONE Switch -- SELECT speaker or phone
position as desired.
6. ADF Pushbutton -- PUSH in and note relative bearing on ADF
indicator.
7. HDG Control -- SET goniometer-indicator dial so that index
indicates 0°, magnetic, or true heading of airplane. Pointer then
indicates relative, magnetic, or true bearing to station .
. ~.. 8. VOL Control -- ADJUST to desired listening level.
NOTE
When switching stations, place function pushbutton in the
REC position. Then, after station has been selected, place
function pushbutton in the ADF position to resume auto-
matic direction finder operation. (This practice prevents
the bearing indicator from swinging back and forth as
frequency dial is rotated.)
TO TEST RELIABILITY OF AUTOMATIC DIRECTION FINDER:
1.
ADF Pushbutton -- PUSH in and note relative bearing on indicator.
2. TEST Pushbutton -- PUSH in and hold TEST button unit indicator
pointer slews off indicated bearing at least 10 to 20 degrees.
3. TEST Pushbutton -- RELEASE and OBSERVE that indicator
pointer returns to the same relative bearing as in step (1).
TO OPERATE BFO:
1.
OFF/VOL Control -- ON.
2. ADF SPEAKER/PHONE Switch -- SELECT speaker or phone
position.
3. BFO Pushbutton -- PUSH in.
4. 1-2 Selector Switch-- SELECT 1 position to activate PRI frequency
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