TM 55-1510-220-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.
b.
Defective ADF receiver.
c.
Defective ADF control unit.
K21.
No ADF audio heard in headsets and tuning meter does not deflect.
a.
No power to ADF radio set.
b.
Defective ADF receiver.
c.
Defective ADF control panel.
d.
Defective ADF sense antenna.
K22.
Radio magnetic indicator does not indicate magnetic bearing to station with sin gle or double
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 c ompass heading of
aircraft (corrected for compass deviation).
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