Aiwa Z-L520 Service Manual page 30

ADJUSTMENT < TUNER / DECK / FRONT >
QQ
< TUNER SECTION >
3 7 63 1515 0
1. Clock Frequency Check
Settings : • Test point :
Method : Set to AM 1710 kHz<U> or MW 1602 kHz<EZ,K>
and check that the test point is 2160 kHz ± 45 kHz
<U> or 2025 kHz ± 45kHz<EZ,K>.
2. AM VT Check<U>
Settings : • Test point :
Method : Set to AM 1710 kHz and check that the test point is
less than 8.5 V. Then set to AM 530 kHz and check
that the test point is more than 0.6 V.
3. MW VT Check<EZ,K>
Settings : • Test point :
Method : Set to MW 1602 kHz and check that the test point is
less than 8.0 V. Then set to MW 531 kHz and check
that the test point is more than 0.6 V.
4. LW VT Adjustment<EZ,K>
Settings : • Test point :
• Adjustment location : L942
Method : Set to LW 144 kHz and adjust L942 so that the test
point becomes 1.3 V ± 0.05 V. Then set to LW 290
kHz and check that the test point is less than 8.0 V.
5. FM VT Adjustment<U>
Settings : • Test point :
• Adjustment location : L906
Method : Set to FM 108.0 MHz and adjust L906 so that the test
point becomes 7.0 V ± 0.1 V. Then set to FM 87.5
MHz and check that the test point is more that 0.4 V.
TE
L 13942296513
6. FM VT Check<EZ,K>
Settings : • Test point :
Method : Set to FM 108.0 MHz and check that the test point is
less than 8.0 V. Then set to FM 87.5 MHz and check
that the test point is more that 0.5 V.
7. AM Tracking Adjustment<U>
Settings : • Test point :
• Adjustment location : L951 (1/3)
Method : Set to AM 1000 kHz and adjust L951 (1/3) so that the
test point becomes maximum.
8. MW Tracking Adjustment<EZ,K>
Settings : • Test point :
• Adjustment location : L951 (1/3)
Method : Set to MW 999 kHz and adjust L951 (1/3) so that the
test point becomes maximum.
www
.
http://www.xiaoyu163.com
TP2 (CLK)
TP1 (VT)
TP1 (VT)
TP1 (VT)
TP1 (VT)
TP1 (VT)
TP8 (Lch), TP9 (Rch)
TP8 (Lch), TP9 (Rch)
x ao u163
y
i
http://www.xiaoyu163.com
2 9
8
9. LW Tracking Adjustment<EZ,K>
Settings : • Test point :
• Adjustment location :
L941 ........................... 144 kHz
TC942 ......................... 290 kHz
Method : Set up TC942 to center before adjustment. The level at
144 kHz is adjusted to MAX by L941. Then the level
at 290 kHz is adjusted to MAX by TC942.
10. FM Tracking Adjustment<U>
Settings : • Test point :
• Adjustment location : L903
Method : Set to FM 87.5 MHz and adjust L903 so that the test
point is less than 9dBµV.
11. FM Tracking Check<EZ,K>
Settings : • Test point :
Method : Set to FM 98.0 MHz and check that the test point is
less than 13dbµV.
12. AM IF Adjustment
Settings : • Test point :
• Adjustment location :
L802 ........................... 450 kHz
13. DC Balance / Mono Distortion Adjustment
Settings : • Test point :
• Adjustment location : L801
• Input level :
Method : Set to FM 98.0 MHz and adjust L801 so that the
voltage between TP3 and TP4 is 0 V ± 500 mV.
Next, check that the distortion is less that 1.2%.
Q Q
3 6 7 1 3 1 5
14. Output Level Check
<AM / MW>
Settings : • Test point :
• Input level :
Method : Set to AM 1000 kHz<U> or MW 999 kHz<EZ,K> and
check that the test point is 40 mV ± 3dB.
<FM>
Settings : • Test point :
• Input level :
Method : Set to FM 98.0 MHz and check that the test point is
200 mV ± 3dB<U> or 140 mV ± 3dB<EZ,K>.
15. FM Separation Check
Settings : • Test point :
• Input level :
Method : Set to FM 98.0 MHz and check that the test point is
more than 25dB<U> or 12dB<EZ,K>.
co
.
– 30 –
9 4 2 8
TP8 (Lch), TP9 (Rch)
TP8 (Lch), TP9 (Rch)
TP8 (Lch), TP9 (Rch)
TP8 (Lch), TP9 (Rch)
TP3, TP4 (DC balance)
60dBµV
0 5 8 2 9 9 4 2 8
TP8 (Lch), TP9 (Rch)
74dBµV
TP8 (Lch), TP9 (Rch)
60dBµV
TP8 (Lch), TP9 (Rch)
60dBµV
m
9 9
9 9