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mode transmit frequency (see Table 9) to be used, and
“XX” represents the current transmit deviation setting in
radio memory. There is no direct correlation between
the value of “XX” and the actual deviation in kHz; how-
ever, the deviation level increases with the “XX” value.
Connect the radio to a modulation analyzer, and
set the analyzer for peak deviation measurement with a
15 kHz low-pass filter, no de-emphasis, and no high-
pass filtering. Press Mode to scroll to “DEV2 XX.”
Apply a 1-volt rms, 1 kHz tone to the microphone audio,
and key the radio with the PTT button. Adjust by press-
ing VOL up or down to zero the deviation reading to less
than or equal to +2.4 kHz; then dekey the radio. Press
HOME to save the new value and exit back to the “DEV”
menu.
Press Mode to scroll through the three test mode
frequencies (DEV1 XX, DEV2 XX, and DEV3 XX) and
adjust each as described above. Deviation levels with
all the various signalling types can also be checked by
returning to the “TST FREQ” menu and accessing the
desired test mode modulation and frequency (refer to
paragraph 4.9). (All modulation types should be less
than ±2.4 kHz peak deviation on all frequencies.)
NOTE
Single Tone deviation cannot be checked except by
using an IBM PC as described in ALIGNMENT VIA
IBM PERSONAL COMPUTER section VII.
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