AIWA AVD35
Manual de Servicio

ELECTRICAL ADJUSTMENT

PRACTICAL SERVICE FIGURE

TUNER C.B
FFE801

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< TUNER SECTION >
<FM SECTION> Signal to noise ratio: Distortion: (Input: 60dB) Stereo separation: Intermediate frequency: More than 62dB (at 98.0MHz) Less than 2.0% (at 98.0MHz) More than 22dB (at 98.0MHz) 10.7MHz

TP5

4

L772 TP1

L771

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TC942 IC771 L981 L942 TP2 TP3 L941 TP4 TP6

<MW SECTION> Sensitivity: (S/N 20dB) Signal to noise ratio: (Input: 74dB) Distortion: Intermediate frequency: <LW SECTION> Sensitivity:

Less than 60dB (at 600kHz) Less than 58dB (at 1000/1400kHz) More than 36dB (at 1000kHz) Less than 1.5% (at 1000kHz) 450kHz

Less than 70dB (at 144kHz) Less than 68dB (at 198kHz) Less than 66dB (at 290kHz)

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< TUNER SECTION >
1. Clock Frequency Check Settings: Method:

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7. LW Tracking Adjustment Settings: � Test point: � Adjustment location: Method: Set to LW 144kHz and adjust L941 so that the test point becomes maximum. Then set to LW 290kHz and adjust TC942 so that the test point becomes maximum.

� Test point: TP2 (CLK IC771 pin30) Set to AM 1602kHz and check that the test point becomes 2052kHz±45Hz.

2. MW VT Check Settings: � Test point: TP1 (VT) Method: Set to AM 1602kHz and check that the test point is less than 8.0V. Then set to AM 531kHz and check that the test point is more than 0.6V.

3. MW IF Adjustment Settings: � Test point: TP5, TP6 L772 .............................................. 450kHz 4. MW Tracking Adjustment Settings: � Test point: TP5, TP6 � Adjustment location: L981 (1/3) Method: Set to AM 999kHz and adjust L981 so that the test point becomes maximum. 5. FM VT Check Settings: � Test point: TP1 (VT) Method: Set to FM 87.5MHz, 108.0MHz and check that the test point is more than 0.5V (87.5MHz) and less than 8.0V (108.0MHz). 6. LW VT Adjustment Settings: � Test point: TP1 (VT) � Adjustment location: L942 Method: Set to LW 144kHz and adjust L942 so that the test point is 1.3V±0.05V. Then set to 290kHz and check that the test point is less than 8.0V.

8. DC Balance/Mono Distortion Adjustment Settings: � Test point: TP3, TP4 � Adjustment location: L771 � Input level: 60dB Method: Set to FM 98.0MHz and adjust L771 so that the voltage between TP3 and TP4 becomes 0V±0.04V. Next, check that the distortion is less than 1.3%.

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