Aiwa XR-M55 Service Manual page 53

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ADJUSTMENT — 1 <TUNER
MAIN C.B
< TUNER SECTION >
1.
: U, LH, HR, EZ, K>
Clock Frequency Check 5.
Settings: * Test point : TP3 (CLK)
Method: Set to AM 1710kHz(U,LH), MW 1602kHz(HR,
EZ, K) and check that the test point is 2160kHz +
45Hz(U, LH), 2052kHz + 45Hz(HR, EZ, K).
MW VT Check
Settings: * Test point : TP4 (VT)
Method: Set to MW 1710kHz (U, LH), MW 1602kHz(EZ, 6.
K, HR) and check that the test point is less than
8.5V (U, LH, HR), less than 8.0 V(EZ, K).
Then set to 530 kHz(U, LH, ), 531 kHz(EZ, K,HR)
and check that the test point is more than 0.6 V
(U, LH, EZ, K), more than 0.3 V(HR).
AM(MW) Tracking Adjustment
Settings: * Test point: TP8 (TU-LCH)
TP9 (GND)
TP10 (TU-RCH)
* Adjustment location : L981
Method: Set to MW 1000kHz(U, LH), MW 999kHz(HR, 7.
EZ, K) and adjust L981 so that the test point
becomes maximum.
AM IF Adjustment
Settings: * Test point: TP8 (TU-LCH)
TP9 (GND)
TP10 (TU-RCH)
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— 69 —
TP8(TU-L)
TP10(TU-R)
TP9(GND)
LW VT Adjustment<EZ, K>
Settings: * Test point : TP4 (VT)
* Adjustment location : L942
Method: Set to LW 144kHz and adjust L942 so that the
test point becomes 1.3 V + 0.05 V.
Then set to 290kHz and check that the test
point is less than 8.0 V.
LW Tracking Adjustment<EZ, K>
Settings: * Test point: TP8 (TU-LCH)
TP9 (GND)
TP10 (TU-RCH)
« Adjustment location :
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TOAD sicscicasstesarsincocane seuss cecteeenenoedctenecte 290kHz
Method: Set up TC942 to center before adjustment. The
level at 144kHz is adjusted to MAX by L941.
Then the level at 290kHz is adjusted to MAX
by TC942.
FM VT Check
Settings: * Test point : TP4 (VT)
Method: Set to FM 87.5MHz and check that the test point
is more than 0.5V. Then set to 108.0MHz and
check that the test point is less than 8.0 V.