ADJUSTMENT <TUNER>
CG TUNER C.B
76
CN601
FFE801
TP9
(RCH)
L771L772
TP1
L981(VT)
IC771
TP2
(CLK)
TP8 TP3
(LCH)(DC BALANCE)
(1/3)
TP4
(DC BALANCE)
3 5 6 71732 4
< TUNER SECTION >
1. Clock Check5. FM Tracking Check
Settings : Y Test point : TP2(CLK)Settings : Y Test point : TP9(Lch), TP9(Rch)
Method : Set to AM 1710kHz and check that the test point isMethod : Y Set to FM 98.0MHz and check that the test point is
2160kHz ? 45Hz.less than 9.0dB.
2. AM VT Check6. AM IF Adjustment
Settings : Y Test point : TP1(VT)Settings : Y Test point : TP8(Lch), TP9(Rch)
Method : Set to AM 1710kHz and AM 530kHz and checkY Adjustment location :
that the test point is less than 8.5V(1710kHz) andL772 ................................................450kHz
more than 0.6V(530kHz).
7. DC Balance / Mono Distortion Adjustment
3. AM Tracking AdjustmentSettings : Y Test point : TP3, TP4 (DC Balance)
Settings : Y Test point : TP8(Lch), TP9(Rch) TP8(Lch), TP9(Rch) (Distortion)
Y Adjustment location :Y Adjustment location : L771
L981(1/3) ......................................1000kHzY Input level : 60dB?V
Method : Set to MW 1000kHz and adjust L981(1/3) so that theMethod : Set to FM 98.0MHz and adjust L771 so that the
test point is max.voltage between TP3 and TP4 becomes 0V ? 0.04V.
Next, check that the distortion is less than 1.3%.
4. FM VT Check
Settings : Y Test point : TP1(VT)
Method : Set to FM 108.0MHz and check that the test point is
less than 8.0V.
Then, set to FM 87.5MHz and check that the test point
is more than 0.5V.
� 32 � |
ACEC
AIWA
