Yaesu FT-208R, Руководство по техническому обслуживанию

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SERVICING
C. Squelch Adjustment
1 . Apply a -8 dB signal with 1 kHz modulation
@ ± 3 . 5 kHz deviation to the ANT jack, and
set the frequency to 1 46 MHz ( 1 45 MHz).
Then set the transceiver to the same frequen­
cy.
2. Rotate the SQL control knob fully counter­
clockwise, and adjust VR103 so that the
squelch just opens.
III. Transmitter Alignment
A. Power Amplifier Alignment
1 . Connect a dummy load/wattmeter to the
ANT jack, and set the transceiver to 1 46 MHz
(model B 145 MHz).
2. Connect a DC voltmeter to the emitter of
Q101 . Refer to the Transmitter Section Align­
ment Point photo on the next page.
3 . Set the HI/LOW switch t o the LOW position
and close the PTT switch. Now adjust T204 ,
T106 , T107 , T20s , T109 and T110 for maximum
DC voltage on the meter.
4. Set the HIGH/LOW switch to the HIGH
position, and adjust L1o2 , L106 and TC101 for
a maximum RF power reading on the watt­
meter.
B. Deviation Adjustment
1 . Connect a dummy load through a directional
coupler to the ANT jack, and a portion of the
output from the directional coupler to the
deviation meter. Apply a 1 kHz 25 m V signal
to the external microphone connector from
an audio oscillator.
2. Adjust VR202 for a deviation of ±4.5 kHz on
the deviation meter (refer to Figure 2).
VR103
T103
RECEIVER SECTION ALIGNMENT POINTS
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