Sony WM-FX671 Service Manual page 12

TUNER SECTION
[AM]
BAND switch : AM
AM RF signal
generator
30% amplitude modulation by 400Hz
signal.
Output level : as low as possible
[FM]
BAND : FM
FM RF signal
generator
22.5kHz frequency deviation by 400Hz signal.
Output level : as low as possible
set
2 REMOTE jack (J701)
• Repeat the procedures in each adjustment several times.
AM FREQUENCY COVERAGE ADJUSTMENT
Adjust for a maximum reading on level meter.
T1
AM IF ADJUSTMENT
Adjust for a maximum reading on level meter.
T2
FM FREQUENCY COVERAGE ADJUSTMENT
Adjust for a maximum reading on level meter.
L2
0dB=1µV
Put the lead-wire
antenna close to
the set.
0.01 µ F
to ANT (TP1)
level meter
16 Ω
+
–
531 kHz
450 kHz
76 MHz
FM VCO Adjustment
Procedure :
FM RF signal
generator
Carrier frequency : 98MHz
IModulation : no modulation
Output level : 0.1V (100dB)
1. Connect frequency counter to the positions shown below.
2. Tune the set to 98 MHz.
3. Adjust RV1 so that the value of the frequency counter reading
becomes 19 kHz.
TP5
(IC2 Pin !™ )
TP6
(IC2 Pin 9 )
Specification Value :
Frequency counter
18,900 – 19,100 Hz
Adjustment Location: MAIN board (See page 11)
— 12 —
0.01 µ F
to ANT (TP1)
Frequency counter
1 µ F
+
–
100k Ω