Aiwa CX-NR71, Service Manual

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<TUNER Adjustment>
1. VT Check (MW)
Requirements
• Measuring instrument: Digital multimeter
Test points: VT, GND
1) Connect the digital multimeter between VT and GND.
2) Set the function to MW, and tune the receiving frequency of the unit at 1,602 kHz.
3) Check that the digital multimeter ranges under 8 V.
4) Tune the receiving frequency of the unit at 531 kHz.
5) Check that the digital multimeter ranges above 0.5 V.
2. VT Adjustment (LW)
Requirements: Same as above.
• Adjustment point: L942
1) Connect the digital multimeter between VT and GND.
2) Set the function to FM, and tune the receiving frequency of the unit at 144.0 kHz.
3) Adjust L942 so that the digital multimeter ranges at 1.3
±
0.05 V.
3. 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 108.0 MHz.
3) Adjust L907 so that the digital multimeter ranges at 7.0
±
0.1 V.
4) Tune the receiving frequency of the unit at 87.5 MHz.
5) Check that the digital multimeter ranges under 0.5 V.
4. CLOCK Check (MW)
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 MW, and tune the receiving frequency of the unit at 1,710 kHz.
3) Check that the frequency counter ranges at 2,160 kHz
±
45 Hz.
ELECTRICAL ADJUSTMENT -2/7