SONY WMFX485
Instrukcja Serwisowa

TUNER SECTION

0 dB=1 µV

FM VCO Adjustment Procedure :
FM RF signal generator 0.01µF

[AM] RADIO ON/BAND button : AM
AM RF signal generator

Put the lead-wire antenna close to the set.

to ANT (TP1) Carrier frequency : 98MHz Modulation : No moduration Output level : 0.1V (100dB)

30% amplitude modulation by 400Hz signal. Output level : as low as possible

1. 2. 3.

Connect the frequency counter to the positions shown below. Turn the set to 98 MHz. Adjust RV1 for 19,000 Hz reading on the frequency counter.

[FM] RADIO ON/BAND button : FM
FM RF signal generator 0.01µF to ANT (TP1)

Specification Value: Digital frequency counter 18,900 to 19,100 Hz

Frequency counter TP23 1µF
+ �

22.5kHz frequency deviation by 400Hz signal. Output level : as low as possible Level meter 16� set
+ � 2 REMOTE jack (J701)

(IC7 pin !�) 100� IC7 pin 9

Adjustment Location : [TUNER BOARD] � SIDE A �

� Repeat the procedures in each adjustment several times, and the frequency coverage and tracking adjustments should be finally done by the trimmer capacitors. AM TRACKING ADJUSTMENT Adjust for a maximum reading on level meter. L4 621kHz CT1 1,395kHz FM IF ADJUSTMENT Adjust for a maximum reading on level meter. L3 10.7MHz FM VOLTAGE ADJUSTMENT 1.05 to 1.15 V L2 76MHz

L2 : FM Voltage Adjustment L3 : FM IF Adjustment

TP1

CT1 : AM Tracking Adjustment

TP13 IC7 L4 : AM Tracking Adjustment

RV1 : FM VCO Adjustment

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