Aiwa XR-EM30 Service Manual page 40

ELECTRICAL ADJUSTMENT -4/8
TUNER ADJUSTMENT
PART SIDE
L952
L953
L941
L942
TC942
L905
L902
L904
L901
L907
1. Clock Check
Requirements
Measuring equipment: Frequency counter
Test point: TP1 (CLOCK), GND
1) Adjust the reception frequency of the main unit to 1710KHz.
2) Check that the test point frequency is 2160±0.045KHz.
2. Vt Adjustment (LW)
Requirement
Measuring equipment: Digital multi-meter
Test point: TP4 (R962), GND
Adjustment point: L942
1) Adjust the reception frequency of the main unit to 144KHz.
2) Adjust L942 until the test point voltage (VT) is 1.3V±0.05V.
3. Vt Check (MW)
Requirement
Measuring equipment: Digital multi-meter
Test point: TP4 (R962), GND
1) Adjust the reception frequency of the main unit to 531KHz.
2) Check that the test point (VT) voltage is about 0.5V.
3) Adjust the reception frequency of the main unit to 1602KHz.
4) Check that the test point (VT) voltage is below 8.0V.
4. Vt Adjustment (FM)
Requirement
Measuring equipment: Digital multi-meter
Test point: TP4 (R962), GND
Adjustment point: L907
1) Adjust the reception frequency of the main unit to 108.0MHz.
2) Adjust L907 until the test point voltage (VT) is 7.0V±0.1V.
3) Adjust the reception frequency of the main unit to 87.5MHz.
4) Check that the test point (VT) voltage is about 0.5V.
CN991
7
IC991
2
8
IC801
6
L802
4
9
PATTERN SIDE
TP8 (LCH)
11 PIN
TP9
(RCH)
12
PIN
TP2
)
TP1(
CLOCK
pin
24
R815
IC801
TP3
TP
GND
TP
GND
VT
GND
VT
GND
-40-
TP4
GND
R962
FREQUENCY COUNTER
Hz
DIGITAL MULTIMETER
V
DIGITAL MULTIMETER
V
DIGITAL MULTIMETER
V
1 2 3 4
6 7 8 9
6 7 8 9
1
2 3 4
5