AIWA NSXVC78
Service Manual

ADJUSTMENT (TUNER / DECK / FRONT)
A MAIN C.B
9 8
9 4 2 5 3

L802 L801 TP3 IC80124 TP2 (CLK) R815 TP4 L942

TC943

L941

TC941

L953 4

L952

TP1 FFE831 (VT)
GND TP8 (LCH) TP9 (RCH) 3 5 7 8 9 IC601

1

2

4

6

< TUNER SECTION >
1. Clock Frequency Check Settings : � Test point : TP2 (CLK) Method : Set to MW 1602kHz and check that the test point is 2052kHz ± 45Hz. 2. MW VT Adjustment Settings : � Test point : TP1 (VT) � Adjustment location : L953 Method : Set to MW 1710kHz and adjust L953 so that the test point become 8.3V ± 0.05V. Then set to MW 530kHz and check that the test point is more than 0.3V. 3. MW Tracking Adjustment Settings : � Test point : TP8 (Lch), TP9 (Rch) � Adjustment location : L952............................... 603kHz TC941............................ 1404kHz Method : Set up TC941 to center before adjustment. Adjust L952 so that level at 603kHz become maximum. Then adjust TC941 so that the level at 1404kHz becomes maximum. 4. SW VT Adjustment Settings : � Test point : TP1 (VT) � Adjustment location : L942 Method : Set to SW 17.9MHz and adjust L942 so that the test point becomes 8.5V ± 0.2V. Then set to SW 5.9MHz and check that the test point is more than 0.3V. 5. SW Tracking Adjustment Settings : � Test point : TP8 (Lch), TP9 (Rch) � Ajustment location : L941............................... 5.9MHz TC943.............................17.9MHz Method : Set up TC943 to center before adjustment. Adjust L941 so that level at 5.9MHz becomes maximum. Then adjust TC943 so that the level at 17.9MHz becomes maximum. 6. FM VT Check Settings : � Test point : TP1 (VT) Method : Set to FM 108.0MHz and check that the test point is less than 8.0V. Then set to FM 87.5MHz and check that the test point is more than 0.5V. 7. FM Tracking Check Settings : � Test point : TP8 (Lch), TP9 (Rch) Method : Set to FM 98.0MHz and check that the test point is less than 9.0dBµV. 8. AM IF Adjustment Settings : � Test point : TP8 (Lch), TP9 (Rch) � Adjustment location : L802............450kHz 9. DC Balance / Mono Distortion Adjustment Settings : � Test point : TP3, TP4 (DC Balance) TP8 (Lch), TP9 (Rch) � Adjustment location : L801 � Input level : 60dBµV 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.

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