Cessna TURBO CENTURION T210M 1978 Pilot Operating Handbook page 286

CESSNA 400 ADF
(TYPE R-446A)
PILOT'S OPERATING HANDBOOK
SUPPLEMENT
or 2 to activate SEC frequency that is transmitting keyed CW
signals (Morse Code). / ~.
5. VOL Control -- ADJUST to desired listening level.
NOTE
A 1000-Hz tone is heard in the audio output when CW signal
(Morse Code) is tuned in properly.
SECTION 5
PERFORMANCE
There is no change to the airplane performance when this avionic
equipment is installed. However, the installation of an externally mounted
antenna or several related external antennas, will result in a minor
reduction in cruise performance.
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