Yaesu FT-5100, Technical Supplement

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Servicing
1-kHz tone to the antenna connector. Adjust
VR405 on the IF Unit so that all S-meter
segments are just on.
UHF S-Meter Calibration
D Tune the transceiver and RF signal gener­
ator to the center of the UHF band and with
the same injection level and modulation,
adjust VR406 so that all S-meter segments
are just on.
VHF Scanner Center-Stop
D
With both the transceiver and signal gener­
ator tuned to the center of the VHF band, set
the signal generator for 30-dBµ
RF modu­
lated with ± 3.5-kHz deviation of a 1-kHz
tone.
D
Connect the DC voltmeter (3-V range) be­
tween TP401 (+) and TP402 (-) on the IF
Unit, and adjust VR403,
if
necessary, for
zero volts on the meter.
D
Reduce the injection level to 10 dBµ, then
press the
UP or DWN button on the micro-
2-4
phone for more than
1;2
second to start scan­
ning. Confirm that scanning stops at the
injection frequency.
UHF Scanner Center-Stop
D
Move the DC voltmeter to TP403 (+) and
TP404, tune the transceiver and signal gen­
erator tuned to the center of the UHF band
and perform the above (VHF) steps, adjust­
ing VR404 for zero volts with 30 dBµ injec­
tion.
Single-Band/Dual-Receive Sensitivity
D
With both the transceiver and signal gener­
ator tuned to the center of
either band, set
the signal generator for 30-dBµ RF modu­
lated with ± 3.5-kHz deviation of a 1-kHz
tone at the antenna connector.
D
Adjust T1008 on the Main Unit for optimum
12-dB SIN AD, then confirm -6 dBµ or better
12-dB SINAD at the high and low band
edges.
FT- 5100 Technical Supplement
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