TM 55-1510-221-MTF
a.
Defective course deviation indicator.
b.
Defective course deviation indicator switching relay.
K20. ADF radio set inoperative.
a.
No power to ADF radio set.
K21. No ADF audio heard in headsets and tuning meter does not
deflect.
a.
Defective ADF receiver.
b.
Defective ADF control panel.
c.
Defective ADF sense antenna.
K22. Radio magnetic indicator does not indicate magnetic
bearing to station with single needle switch set to ADF.
a.
Defective ADF receiver.
b.
Defective RMI.
c.
Defective ADF fixed-loop antenna.
d.
Defective ADF-VOR switch on RMI.
e.
Defective ADF control panel.
K23. ADF single needle pointer does not return to station
bearing.
a.
Defective RMI
K24. Quality of ADF reception is poor.
a.
Defective ADF control panel.
b.
Defective audio control panel.
c.
Defective ADF receiver.
K25. Heading on course deviation indicator does not agree with
magnetic compass heading of aircraft (corrected for
compass deviation).
a.
Defective gyro compass set
b.
Incorrect compass deviation card.
K26. Copilot's radio magnetic indicator heading does not agree
with pilot's horizontal situation indicator heading within two
degrees.
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