Aiwa NSX-SZ70 Service Manual page 30

< TUNER SECTION >
1. Clock Frequency Check
Settings : • Test point :
Method : Set to MW 1602kHz and check that the test point is
2052kHz ± 45Hz.
2. MW VT Check
Settings : • Test point :
Method : Set to MW 1602kHz and check that the test point is less
than 8.0V. Then set to MW 531 kHz and check that the
test point is more than 0.6 V.
3. MW Tracking Adjustment
Settings : • Test point : TP8(Lch), TP9(Rch)
• Adjustment location :
L951(1/3)........................ 999kHz
Method : Set to AM 999kHz and adjust
L951(1/3) so that the test point is max.
4. LW VT Adjustment
Settings: • Test point :
• Ajustment location : L942
Method : Set to LW 144kHz and adjust L942 so that the test point
becomes 1.3V ± 0.05 V.
Then set to LW 290kHz and check that the test point is
less than 8.0V.
5. LW Tracking Ajustment
Settings : • Test point :
• Ajustment location :
L941................................144kHz
TC942..............................290kHz
Method: Set to 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.
6. FM VT Check
Settings : • Test point :
Method : Set to FM 108.0MHz and check that the test
less than 8.0V.
Set to FM 87.5MHz and check that the test point is more
than 0.5V.
7. FM Tracking Check
Settings : • Test point :
Method : Set to FM 98.0MHz and check that the test point is less
than 9.0dBµV.
8. MW IF Adjustment
Settings : • Test point :
• Adjustment location :
• Input level :
Method : Adjust L802 so that the output becomes max.
9. DC Balance / Mono Distortion Adjustment
Settings : • Test point :
• Adjustment location :
• Input level :
Method : Set to FM 98.0MHz and adjust L801 so that the
voltage between TP3 and TP4 becomes 0V ± 0.3V.
Next, check that the distortion is minimum.
All manuals and user guides at all-guides.com
TP2 (CLK)
TP1 (VT)
TP1 (VT)
TP8(Lch),TP9(Rch)
TP1 (VT)
point is
TP8(Lch), TP9(Rch)
TP8(Lch), TP9(Rch)
L802
Variable
TP3, TP4
(DC Balance)
TP8(Lch), TP9(Rch)
(Distortion)
L801
60dBµV
- 30 -
< DECK SECTION >
10. Tape Speed Adjustment (DECK 2)
Settings : • Test tape :
• Test point :
• Adjustment location : SFR1
Method : Play back the test tape and adjust SFR1 so that
the frequency counter reads 3000Hz ± 5Hz(FWD)
and ± 45Hz(REV) with respect to forward speed.
11. Head Azimuth Adjustment (DECK 1, DECK 2)
Settings : • Test tape :
• Test point :
• Adjustment location :
Method : Play back the 10kHz signal of the test tape and adjust
screw so that the output becomes maximum. Next,
perform on each FWD PLAY and REV PLAY mode.
12. PB Frequency Response Check (DECK 1, DECK 2)
Settings : • Test tape : TTA–300 (315/10kHz)
• Test point : TP10(Lch), TP11(Rch)
Method : Play back the 315Hz and 10kHz signals of the test tape
and check that the output ratio of the 10kHz signal with
respect to that of the 315Hz signal is within 0 ± 3dB.
13. REC/PB Frequency Response Adjustment (DECK 2)
Settings : • Test tape : TTA–602 (Normal)
• Test point : TP10(Lch), TP11(Rch)
• Input signal : 1kHz / 10kHz (LINE IN)
• Adjustment location :
Method : Apply a 1kHz signal and REC mode. Then adjust OSC
attenuator so that the output level at the test points
becomes 9.0mV. Record and play back the 1kHz and
10kHz signals and adjust SFRs so that the output level
of the 10kHz signals becomes 0dB ± 0.5dB with respect
to that of the 1kHz signal.
14. REC/PB Frequency response Check (DECK 2)
Settings : • Test tape : TTA-615 (CrO
• Test point : TP10(Lch), TP11(Rch)
• Input signal : 1kHz/10kHz (LINE IN)
Method : Apply a 1kHz signal and REC mode. Then adjust OSC
attenuator so that the output level at the test points
becomes 9.0mV. Record and play back the 1kHz and
10kHz signals and check that the output is 0dB ± 2dB.
15. REC/PB Sensitivity Check (DECK 2)
Settings : • Test tape : TTA-615 (CrO
• Test point : TP10(Lch), TP11(Rch)
• Input signal : 1kHz (LINE IN)
Method : Apply a 1kHz signal and REC mode. Then adjust OSC
attenuator so that the output level at the test points
becomes 90mV. Record and play back the 1kHz signal
and check that the output is -1dB ± 3dB.
16. µ-CON OSC Adjustment
Settings : • Test point :
• Adjustment location :
Method : Insert AC plug with pressing TUNER function key.
Adjust L101 so that the frequency across the test point is
208.8Hz ± 0.2Hz.
TTA–100(3kHz)
TP10(Lch), TP11(Rch)
TTA–300 (315/10kHz)
TP10(Lch), TP11(Rch)
Head azimuth
adjustment screw
SFR351 (Lch)
SFR352 (Rch)
)
2
)
2
TP5(K-SCAN)
L101