Hz
FREQUENCY COUNTER
TP
GND
<TUNER SECTION>
IC801
IC991
L954
L955
L907
L904
L802
CN991
IC801
CN991
TP1(24pin)
TP2
TP3
R815
TP4
R962
TP9 12pin
TP8 11pin
GND 2pin
TUNER C.B (PART SIDE) TUNER C.B (PATTERN SIDE)
① ②③
⑤ ⑥⑦
⑤ ⑥⑦
①
② ③
④
L903
⑥
⑦
⑤
②
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 (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 1.5V.
3.VT CHECK (AM)
Measuring equipment: Digital multi-meter
Test point: TP4 (R962), GND
(1) Adjust the reception frequency of the main unit to 530KHz.
(2) Check that the test point (VT) voltage is about 0.5V.
(3) Adjust the reception frequency of the main unit to 1710KHz.
(4) Check that the test point (VT) voltage is below 9.0V.
Requirement
Measuring equipment: Digital multi-meter
Test point: TP2, 3
(1) Adjust the reception frequency of the main unit to 98.0MHz.
(2) Check that the test point voltage difference between TP2 and TP3 is
0mV
±
500mV.
V
DIGITAL MULTIMETER
VT
GND
V
DIGITAL MULTIMETER
TP2
TP3
V
DIGITAL MULTIMETER
VT
GND
– 41 –
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