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< TUNER SECTION >
1.
Clock Frequency Check
7.
Settings:
¢ Test point :
TP3 (CLK)
Method:
Set to AM 1602kHz (HE, HR), AM 1710kHz
(LH), MW 1602kHz (EZ, K) and check that
the test point is 2052kHz + 45Hz (HE, HR,
EZ, K), 2160kHz + 45Hz (LH).
AM (MW) VT Check
Settings:
¢ Test point:
TP4 (VT)
Method:
Set to AM 1602kHz (HE, HR), AM 1710kHz
(LH), MW 1602kHz (EZ, K) and check that
the test point is less than 8.5V (HE, HR, LH),
less than 8.0V (EZ, K). Then set to AM
531kHz (HE, HR), AM 530kHz (LH), MW
531kHz (EZ, K) and check that the test point is
9.
more than 0.3V (HE, HR), more than 0.6V
(LH, EZ, K).
AM (MW) Tracking Adjustment
Settings:
» Test point:
TP8 (TU-L)
TP9 (GND)
TP10 (TU-R)
¢ Adjustment location :L981
Set to AM 999kHz (HE, HR), AM 1000kHz
(LH), MW 999kHz (EZ, K) and adjust L981
so that the test point becomes maximum.
Method :
AM (MW) IF Adjustment
Settings:
¢ Test point:
TP8 (TU-L)
TP9 (GND)
TP10 (TU-R)
TTD sssssscadavibctentiedesers 450kHz
. LW VT Adjustment <EZ, K>
eR
Settings:
¢ Test point:
TP4 (VT)
¢ Adjustment location :L942
Method:
Set to LW 144kHz and adjust L942 so that the
test point becomes 1.3V + 0.05V. Then set to
LW 290kHz and check that the test point is
less than 8.0V.
. LW Tracking Adjustment <EZ, K>
Settings:
° Test point:
TP8 (TU-L)
TP9 (GND)
TP10 (TU-R)
¢ Adjustment location :
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,
~ 58 —
10.
FM VT Check
Settings:
* Test point:
TP4 (VT)
Method:
Set.to FM 108.0MHz (87.5MHz) and check
that the test point is less than 8.0V (more than
0.5V).
. FM Tracking Check
Settings:
* Test point:
TP8 (TU-L)
TP9 (GND)
TP10 (TU-R)
Method:
Set to FM 98.0MHz and check that the test
point is less than 8dBuV (HE, HR, LH), less
than 13dBuV (EZ, K).
DC Balance / Mono Distortion Adjustment
Settings : « Test point :
TPS (DC), TP6 (DC)
¢ Adjustment location :L771
* Input level :
60dBuV
Method:
Set to FM 98.0MHz and adjust L771 so that
the voltage between TPS and TP6 becomes
OV + 0.04V.
Next, check that the distortion is less than
1.0%.
~,
FM Separation Check
Settings:
»* Test point:
TP8 (TU-L)
TP9 (GND)
TP10 (TU-R)
* Input level :
60dBuV
Method:
Set to FM 98.0MHz and check that the test
point is more than 25dB (HE, HR, LH), more
than 12dB (BZ, K).
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