Electrical Adjustments; Main Vco Frequency Adjustment; Sub Vco Freerun Frequency Adjustment - Sony ICF-SW77 Service Manual

Lw/mw/sw/fm stereo pll synthesized receiver

Hide thumbs Also See for ICF-SW77:

Table of Contents

ICF-SW77

SECTION 3

ELECTRICAL ADJUSTMENTS

I See page 25 for the adjustment location, |

Main VCO Frequency Adjustment

Setup:

Band Selector:

Frequency:

29,999 kHz

MODE Selector: Arbitrary

Connect a jumper wire as following figure.

Procedure:

Adjust CT502 for a 54.5 MHz ± 100 kHz reading.

Unsolder the jumper wire at B+ land side.

Connect this end to ground land.

Confirm the counter reading should be less than 93 MHz.

After the adjustment, remove the jumper wire.

Confirm the digital voltmeter reading should be less than 11.3 V.

Sub VCO Freerun Frequency Adjustment

Setup:

Band selector:

Connect jumper wire as following figure.

frequency counter

Procedure:

Adjust CT503 for a 53.5 MHz ± 100 kHz reading.

Unsolder the jumper wire at B+ land side. Connect this end to ground

land. Confirm the counter reading should be less than 49 MHz.

After the adjustment, remove the jumper wire.

Table of Contents