Tuner Section - Sony WX-C570 Service Manual

TUNER SECTION

0 dB = 1 µV
Cautions during repair
When the tuner unit is defective, replace it by a new one because
its internal block is difficult to repair.
TEST MODE
This set have the test mode function. In the test mode, FM Auto
Scan/Stop Level and AM Auto Scan/Stop Level adjustments can be
performed easier than it in ordinary procedure.
<Set the Test Mode>
1. Set the "POWER SELECT" switch (S501) is "OFF" position.
2. Turn ON the regulated power supply. (All LEDs on the set lights
up, and the clock is displayed.)
3. Push the preset 4 button.
4. Push the preset 5 button.
5. Press the preset 1 button for more than two seconds.
6. Then the display indicates all lights, the test mode is set.
<Release the Test Mode>
1. Push the OFF button.
Note on Adjustment
The adjustments of tuner section, should be performed according
to the following sequence.
1. FM Auto Scan/Stop Level Adjustment
2. FM Stereo Separation Adjustment
3. AM Auto Scan/Stop Level Adjustment
FM Auto Scan/Stop Level Adjustment
Setting :
D-BASS switch
TUNER button
FREQUENCY SELECT switch (UK, E model) : FM 200K
FM RF signal
generator
Carrier frequency : 97.9 MHz
Output level
Mode
Modulation
Procedure :
1. Set to the test mode.
2. Push the TUNER button and set to FM.
L
3. Push the preset 3 button.
PRESET
L
4. Adjust with the volume RV2 on TU1 so that the "FM" indica-
tion turns to "FM2" indication on the display window.
But, in case of already indicated "FM2", turn the RV2 so that
put out light "2" indication and adjustment.
PRESET
L
Adjustment Location : See page 27.
– 25 –
: OFF
: FM
antenna
terminal
0.01 µF
set
: 22 dB (12.6 µV)
: mono
: 1 kHz, 22.5 kHz deviation (30%)
Display
SHUF1
R
Display
SHUF1
R
Display
SHUF1
R