Service manual

28
VL-A111U/AH131U
VL-AH151U/AH161U
6-6-3. VCR circuit adjustment
* Before adjusting the VCR circuit, make sure that the fixed value in 6-3-2 is written in
E
2
PROM.
· Test points on the video circuit board.
POWER CIRCUIT ADJUSTMENT
PROCEDURE
6-6-3-1. Supply voltage
adjustment/check
Turn on power
1. Adjust to CAM 15V
û
2. Check P-CON 4.9V
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û
3. Check P-CON 3.3V
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4. Check P-CON 3.1V
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5. Check DSP 2.65V
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6. Check DSP 1.85V
7. Check LCD 13.2V
8. Check LCD 7V
û
9. Check LCD -15.2V
10. Check CAM -8V
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û
Æ Turn off power.
û
û
1. Adjustment to CAM 15V
Make an adjustment so that the digital voltmeter indicates 15V
± 0.05V.
Measuring instrument Digital voltmeter
Measuring terminal TL905
Adjustment address 32h(VTR ADJ)
Standard 15V ± 0.05V
Measuring instrument Digital voltmeter
Measuring terminal TL901
Adjustment address
Standard 4.9V ± 0.1V
3. Checking of P-CON 3.3V
Ascertain that the digital voltmeter indicates 3.3V ± 0.1V.
Measuring instrument Digital voltmeter
Measuring terminal TL903
Adjustment address
Standard 3.3V ± 0.1V
4. Checking of P-CON 3.1V
Ascertain that the digital voltmeter indicates 3.1V ± 0.1V.
Measuring instrument Digital voltmeter
Measuring terminal TL9718
Adjustment address
Standard 3.1V ± 0.1V
5. Checking of DSP 2.65V
Ascertain that the digital voltmeter indicates 2.65V ± 0.25V.
Measuring instrument Digital voltmeter
Measuring terminal TL916
Adjustment address
Standard 2.65V ± 0.25V
2. Checking of P-CON 4.9V
Ascertain that the digital voltmeter indicates 4.9V ± 0.1V.
POWER CIRCUIT ADJUSTMENT METHOD
Æ Input 7V from DC Jack, and set the power switch to the camera side.
` Do not fail to fix the back light unit before adjusting them.
6. Checking of DSP 1.85V
Ascertain that the digital voltmeter indicates 1.85V ± 0.15V.
Measuring instrument Digital voltmeter
Measuring terminal TL910
Adjustment address
Standard 1.85V ± 0.15V
7. Checking of LCD 13.2V
Ascertain that the digital voltmeter indicates 13.2V ± 0.2V.
Measuring instrument Digital voltmeter
Measuring terminal TL907
Adjustment address
Standard 13.2V ± 0.2V
8. Checking of LCD 7V
Ascertain that the digital voltmeter indicates 7V + 0.4/-0.5V.
Measuring instrument Digital voltmeter
Measuring terminal TL904
Adjustment address
Standard 7V + 0.4/-0.5V
9. Checking of LCD -15.2V
Ascertain that the digital voltmeter indicates -15.2V ± 1V.
Measuring instrument Digital voltmeter
Measuring terminal TL906
Adjustment address
Standard -15.2V ± 1V
10.Checking of CAM -8V
Ascertain that the digital voltmeter indicates -8V ± 0.5V.
Measuring instrument Digital voltmeter
Measuring terminal TL909
Adjustment address
Standard -8V ± 0.5V