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ADJUSTMENT
A
MAIN C.B
VR101
VOLUME
PHONES
8
J101
L251 BAR ANT
5
<RADIO SECTION>
1. AM IF Adjustment
L253 ....................................................................... 450kHz
2. FM IF Adjustment
TC202 ............................................................... 10.70MHz
3. AM VT Check
Settings :
• Test point :
TP4 (VT)
Method :
Set to AM 531kHz and check that the test
point is 1.3V ± 0.3V. Then set to AM 1602
kHz and check that the test point is less than
11V.
4. FM VT Adjustment
Settings :
• Test point :
TP4 (VT)
Method :
Set to FM 87.5MHz and check that the test
point voltage is 3.45V ± 0.55V. Then set to
FM 108.0MHz and check that the test point
voltage is less than 11V.
5. AM Tracking Adjustment
L251 ....................................................................... 630kHz
TC251 .................................................................. 1440kHz
6. FM Tracking Adjustment
L201 .................................................................... 87.5MHz
7. FM VCO Adjustment
Settings :
• Adjustment location : SFR251
• Test point :
TP2 (VCO)
Method : Connect a frequency counter to pin 12 of
IC251. Adjust SFR251 such that the frequency
counter indicates 19kHz ± 100Hz.
2
5
SFR 251
7
1 2
TP1(DET)
8
TP3(FM IF)
SFR 401
IC251
7
TP2(VCO)
TP4(VT)
7
(GND)
1
4
6
2
3
<TAPE PLAYER SECTION>
8. Tape Speed Adjustment
Settings :
• Test tape :
TTA–100
• Test point :
Phones Jack (J101)
• Adjustment location : SFR401
• Volume :
MAX
• DSL :
OFF
• Tape selector :
Normal
Method : Play back the test tape and adjust SFR401 for
3015 ± 10Hz (FWD) and ± 45 (REV).
Then confirm WOW is less than 0.50%.
17
18
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