Tuner Section - Sony Walkman WM-FX571 Service Manual

TUNER SECTION

[AM]
RADIO ON/BAND button : AM
AM RF signal
generator
Put the lead-wire antenna
close to the set.
30% amplitude modulation
by 400Hz signal.
Output level : as low as possible
[FM]
RADIO ON/BAND button : FM
FM RF signal
generator
22.5kHz frequency
deviation by 400Hz signal.
Output level : as low as possible
16 Ω
set
2 REMOTE jack (J701)
• 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
CT1
FM IF ADJUSTMENT
Adjust for a maximum reading on level meter.
L3
FM VOLTAGE ADJUSTMENT
1.05 to 1.15 V
L2
0 dB=1 µV
0.01 µ F
to ANT (TP1)
Level meter
+
–
621kHz
1,395kHz
10.7MHz
76MHz
FM VCO Adjustment
Procedure :
FM RF signal
generator
Carrier frequency : 98MHz
Modulation : No moduration
Output level : 0.1V (100dB)
1. Connect the frequency counter to the positions shown below.
2. Turn the set to 98 MHz.
3. Adjust RV1 for 19,000 Hz reading on the frequency counter.
Specification Value:
Digital frequency counter
18,900 to 19,100 Hz
TP23
(IC7 pin !™ )
IC7 pin 9
Adjustment Location :
[TUNER BOARD] — SIDE A —
L2 : FM
Voltage Adjustment
– 8 –
0.01 µ F
to ANT (TP1)
Frequency counter
1 µ F
+
–
100 Ω
L3 : FM IF Adjustment
CT1 : AM
TP1
Tracking
Adjustment
TP13
IC7
L4 : AM
Tracking
Adjustment
RV1 : FM VCO Adjustment