Sony ICF-SW77 - ELECTRICAL ADJUSTMENTS; Main VCO Frequency Adjustment; Sub VCO Freerun Frequency Adjustment

ICF-SW77
SECTION 3
ELECTRICAL ADJUSTMENTS
I See page 25 for the adjustment location, |
Main VCO Frequency Adjustment
Setup:
Band Selector: AM
Frequency: 29,999 kHz
MODE Selector: Arbitrary
Connect a jumper wire as following figure.
Procedure:
1. Adjust CT502 for a 54.5 MHz ± 100 kHz reading.
2. Unsolder the jumper wire at B+ land side.
Connect this end to ground land.
Confirm the counter reading should be less than 93 MHz.
3. After the adjustment, remove the jumper wire.
4. Confirm the digital voltmeter reading should be less than 11.3 V.
Sub VCO Freerun Frequency Adjustment
Setup:
Band selector: AM
Connect jumper wire as following figure.
frequency counter
Procedure:
1. Adjust CT503 for a 53.5 MHz ± 100 kHz reading.
2. Unsolder the jumper wire at B+ land side. Connect this end to ground
land. Confirm the counter reading should be less than 49 MHz.
3. After the adjustment, remove the jumper wire.
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