Tuner Section - Sony XR-L240 Service Manual

TUNER SECTION

0 dB=1 µV
Cautions during repair
When the tuner unit is defective, replace it by a new one be-
cause its internal block is difficult to repair.
Note: Adjust the tuner section in the sequence shown below.
1. FM RDS S-Meter Adjustment
2. FM Auto Seek/Stop Level Adjustment
3. FM Stereo Separation Adjustment
4. MW Auto Seek/Stop Level Adjustment
FM RDS S-Meter Adjustment
Setting:
[TUNER]
button: FM
FM RF signal
generator
0.01 µ F
Carrier frequency : 98.00 MHz
: 35 dB (56.2 µ V)
Output level
Mode : mono
Modulation : no modulation
Procedure:
1. Set to the test mode. (see page 13)
[TUNER]
2. Push the button and set to FM.
Display
REG
SHUF
[6]
3. Push the button.
4. Adjust RV100 on MAIN board so that the display indication
is "8.4".
Display
REG
SHUF
Specified Value: Display indication: 8.2 to 8.6
Adjustment Location: See page 17.
All manuals and user guides at all-guides.com
antenna jack (ANT100)
set
FM Auto Seek/Stop Level Adjustment
Setting:
[TUNER]
button: FM
FM RF signal
dummy
generator
antenna
50 Ω
50 Ω
Carrier frequency : 98.00 MHz
: 22 dB (12.6 µ V)
Output level
Mode : mono
Modulation : 1 kHz, 22.5 kHz deviation (30%)
Procedure:
1. Set to the test mode. (see page 13)
[TUNER]
2. Push the button and set to FM.
Display
REG
SHUF
3. Adjust with the volume RV3 on TU100 so that the "FM" indi-
cation turns to "FM0" indication on the display window.
But, in case of already indicated "FM0", turn the RV3 so that
put out light "0" indication and adjustment.
Display
REG
SHUF
Adjustment Location: See page 17.
XR-L240
0.1 µ F
antenna
jack (ANT100)
set
15