Sony ICF-SW77 - FM Scan Stop Adjustment; Clock Frequency Adjustment (Microcomputer board)

ICF-SW77
FM Scan Stop Adjustment
Setup:
Band Selector: FM
VOLUME Control: Arbitrary
Clock Frequency Adjustment (Microcomputer board)
Note: When X802 or X803 is replaced, it is necessary to adjust the clock
frequency of IC related to the replaced crystal.
Setup:
FMRFSSG
FM ANT terminal
lPin®ofCN1 \
\ on SIGNAL board, j
Frequency Deviation: ± 22.5 kHz
Carrier Frequency: 93.025 MHz
Output Level: 0.5m V (54 dB)
oscilloscope
frequency counter
• IC801 Clock Frequency Adjustment
1. Connect the regulated dc power supply to the microcomputer board.
2. Press and keep on pressing S801 (TIME SET key).
(Activates 2 MHz clock.)
3. Adjust CT801 for 2,008.0 ±0.2 kHz reading on the frequency
counter.
Note: When S801 is released, 2 MHz clock will stop about 1 second
later.
• IC802 Clock Frequency Adjustment
1. Connect the regulated dc power supply to the microcomputer board.
2. Turn radio on by pressing S806 (ON/OFF key).
3. Adjust CT802 for 2,008.0 ±0.2 kHz reading on the frequency
counter.
Procedure:
1. Tune the set to 93 MHz.
2. Adjust RV301 for 1.5 V down point on the oscilloscope.
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