Panasonic PT-53WX54UJ, Service Manual

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Procedure:
1. Set PTV to Stereo Mode (in the audio menu).
2. Apply the following signal from the RF signal generator: / Video: 100
IRE flat field, 30% modulation. / Audio: 300Hz, 30% modulation, stereo
(left only) (70dB ± 5dB, 75 OPEN, P/S 10dB).
Note:
Set the 30% modulation with the pilot light SW and N.R. switches OFF then turn them ON while testing.
3. Adjust MTS low level separation “SEPAL” DAC data (in the service
menu) until the amplitude of the measured waveform on the scope
is minimum.
4. Apply the following signal from the RF signal generator: / Video: 100
IRE flat field, 30% modulation. / Audio: 3KHz, 30% modulation, stereo
(left only). / (70dB ± 5dB, 75 OPEN, P/S10dB).
Note:
Set the 30% modulation with the P.L and N.R. switches OFF then turn them ON while testing.
5. Adjust MTS High Level Separation “SEPAH” DAC data until the
amplitude of the waveform measured on the scope is minimum.
6. Repeat above steps 2 through 5 until the amplitude is at minimum for
both signals.
17.23. Clock Adjustment (CLOCK)
Preparation:
Connect the frequency counter from TPA9 (A-Board) to cold ground.
Note:
Frequency Counter probe capacitance should be 8pF or less.
Procedure:
1. Turn the PTV “ON” with the A.C. power applied.
2. Measure TPA9 for frequency and record the reading.
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