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1. Clock Frequency Check Settings: � Test point: TP3 (CLK) Method: Set to AM 1710kHz and check that the test point is 2160kHz ±45Hz. 2. AM VT Check Settings: � Test point: TP4 (VT) Method: Set to AM 1710kHz and check that the test point is less than 8.5V. Then set to AM 530kHz and check that the test point becomes more than 0.6V. 3. AM Tracking Adjustment Settings: � Test point: TP8 (Lch), TP9 (Rch) � Adjustment location: L981 (1/3) Method: Set to AM 1000kHz and adjust L981 (1/3) so that the test point becomes maximum. 4. AM IF Adjustment Settings: � Test point: TP8 (Lch), TP9 (Rch) � Adjustment location L772 ...................................................................... 450MHz 5. FM VT Check Settings: � Test point: TP4 (VT) Method: Set to AM 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. 6. FM Tracking Adjustment Settings: � Test point: TP8 (Lch), TP9 (Rch) Method: Set to FM 98.0MHz and check that the test point is less than 9dBµV. 7. DC Balance/Mono Distortion Adjustment Settings: � Test point: TP5, TP6 (DC balance) � Adjustment location: L771 � Input level: 60dBµV Method: Set to FM 98.0MHz and adjust L771 so that the voltage between TP5 and TP6 becomes 0V±0.04V. Next, check that the distortion is less than 1.3%. 8. Output Level Check <AM> Settings: � Test point: TP8 (Lch), TP9 (Rch) Method: Set to AM 1000kHz and check that the test point is 130mV ±3dB. <FM> Settings: Method:
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10. µ-com Clock Adjustment Settings: � Test point: TP5 (CLK), TP2 (GND) � Adjustment location: L331 Method: Connect a frequency counter across TP11 and TP12. Then adjust L331 so that the test point becomes 209.5Hz ±0.5Hz.
� Test point: TP8 (Lch), TP9 (Rch) Set to AM 98.0MHz and check that the test point is 520mV ±3 dB.
9. FM Separation Check Settings: � Test point: TP8 (Lch), TP9 (Rch) � Input level: 60dBµV Method: Set to FM 98.0MHz and check that the test point more than 25dB.
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