TM 55-1510-220-MTF
PROCEDURE
TROUBLESHOOTING
REFERENCE
F.
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° 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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