TM 55-1510-215-MTF
PROCEDURE
TROUBLESHOOTING
REFERENCE
DURING CRUISE (CONT)
c.
Register/zeroize switch - Select desired fill
register.
d.
OFF/ON/TD switch - ON
K17
(interrupted tone should be heard in headset).
e.
Microphone switch - Press
K18
momentarily (interrupted tone in headset
should cease).
f.
Microphone switch - Press (do not talk).
When beep is heard in headset, conduct two
way communication check.
g.
Check the following modes of operation:
(1) Aircraft and ground station-
K19
both in CIPHER mode, operating the air-
craft and the ground station each in turn, as
the transmitting station.
(2) Aircraft and ground station in PLAIN mode,
operating each in turn as the transmitting
station.
(3) Aircraft in CIPHER mode, and the ground
station in PLAIN mode, operating the
ground station as the transmitting station.
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