Panasonic CT-32HX40CB, Руководство по обслуживанию

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Service Adjustments (Electronic Controls, cont.)
Sub Picture YUV output adjustment
Preparation:
1.
Apply a studio color bar pattern.
2. Connect the oscilloscope to TP223(Y).
Procedure:
1.
Push “SPLIT/SIZE” key on the remote control.
2. In Serviceman Mode adjust “Y DRV” data so that
the amplitude “b” is same level as “a”, within
0
±
0.03V.(See Fig. 43).
3. Connect the oscilloscope to TP222(PB).
4. In Serviceman Mode, adjust “UVDRV” data so that
the amplitude “d” is same level as “c”, within
0
±
0.03V. (See Fig. 44)
Clock Adjustment (CLOCK)
Preparation:
Connect the frequency counter from TPA11 (IC001
Pin 50) to cold ground ( ).
Note: Frequency Counter probe capacitance
should be 8pF or less.
Procedure:
1.
Turn the Receiver “OFF” with the AC
power applied.
2. Measure TPA11 (IC001 pin 50) for the frequency of
the waveform and record the reading.
Note: Pin 50 measurement must have at
least four digits of resolution following
the decimal point. Example: 000.0000
3. Turn the Receiver back “ON”.
4. Place the Receiver into Serviceman Mode for
making electronic adjustment, select the Clock
Adjustment DAC (CLOCK).
5. Calculate and set “CLOCK” based on the
following formula:
Note: Pin 50 measurement will not change
regardless of the value stored in
CLOCK.
WHITE
BLACK
a b
MAIN
PICTURE
SUB
PICTURE
Figure 43. TP223 waveform
0
±
0.03V
c
SUB
PICTURE
MAIN
PICTURE
d
Figure 44. TP222 waveform
0
±
0.03V
CLOCK 128 0.450
( )
6
×
10
732.4220
( )
pin50 Hz
[ ]
–
{ }
732.4220
( )
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