TM 55-1510-219-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° 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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