TM 55-1510-221-MTF
PROCEDURE
TROUBLESHOOTING
REFERENCE
G. AVIONICS FLIGHT CHECKS (CONT)
i.
Retune to a low frequency station of known location.
j.
Mode selector switch - ADF The RMI azimuth card
should coincide with the aircraft magnetic heading and
the bearing pointer should indicate the correct
magnetic bearing to station.
k.
Loop control - R, fast speed position (full deflection) of
the loop control Rotate RMI bearing pointer 90° right
and then 90° left of the ADF bearing At both the right
and left displaced bearing indication points, reset the
loop switch to center. The bearing pointer should
return to the original bearing indication at a rate of not
less than 25 degrees per second.
l.
Mode selector switch - LOOP
m.
Loop control - R, slow speed position (half deflection)
of the loop control. Rotate the bearing pointer 360°
left.
Two distinct null positions, 180° from each other
should be encountered.
n.
Stop the bearing pointer on the null that points away
from the station.
o.
Mode selector switch - ADF. The bearing pointer
should.
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