TM 55-1510-222-MTF
P R O C E D U R E
T R O U B L E S H O O T I N G
R E F E R E N C E
G. AVIONICS FLIGHT CHECKS (CONT)
from the lower, middle. and
upper frequency ranges). Es-
tablish two-way communica-
tions on AM and, when possi-
ble, on USB. Obtain signal
quality reports from the other
station and note received sig-
nal quality.
NOTE
The intelligibility of SSB voice operations
becomes degraded when the receiver and
transmitter differ in frequency by a small
amount (approximately 50 Hz). The voice
pitch will sound either too high or too low.
The cause may be either the receiver or
transmitter.
e. Frequency accuracy - Check
as follows:
(1) Station WWV - Select the
frequency that provides
the best signal. The sta-
tion broadcasts on 2.
5000.
5.0000,
15.0000.
20.0000,
and
75.0000
MHz. The higher the fre-
quency selected, the more
accurate
the frequency
check will be.
4-26
