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<TUNER Adjustment>
1. VT Check (AM)
Requirements
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Measuring instrument: Digital multimeter
Test points: VT, GND
1) Connect the digital multimeter between VT and GND.
2) Set the function to AM, and tune the receiving frequency of the unit at 1710kHz.
3) Check that the digital multimeter ranges under 9V.
4) Tune the receiving frequency of the unit at 530kHz.
5) Check that the digital multimeter ranges above 0.5V.
2. VT Adjustment and Check (FM)
Requirements: Same as the above.
•
Adjustment point: L907
1) Connect the digital multimeter between VT and GND.
2) Set the function to FM, and tune the receiving frequency of the unit at 108.0MHz.
3) Adjust L907 so that the digital multimeter ranges at 7.0±0.1V.
4) Tune the receiving frequency of the unit at 87.5MHz.
5) Check that the digital multimeter ranges under 1.5V.
3. CLOCK Check
Requirements
•
Measuring instrument: Frequency counter
Test point: CLOCK (IC801 24PIN), GND
1) Connect the frequency counter between CLOCK and GND.
2) Set the function to AM, and tune the receiving frequency of the unit at 1710kHz.
3) Check that the frequency counter ranges at 2160kHz±45Hz.
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