Clock Adjustment (Clock) - Panasonic P7W Service Manual

4. Apply the following
signal generator:
Video: 100 IRE flat field, 30% modulation.
Audio: 3KHz, 30% modulation, stereo (left only).
(70dB ± 5dB, 75Ω OPEN, P/S 10dB).
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.

Clock Adjustment (CLOCK)

Preparation:
Connect the frequency counter from IC001 MPU
Pin 10 or TPA009, to cold ground (
Note: Frequency Counter probe capacitance should
be 8pF or less.
Procedure:
1. Turn the PTV "ON" with the AC power applied.
2. Measure TPA009 IC001 MPU pin 10 for frequency
and record the reading.
Note: Pin 10 measurement must have at least four
digits of resolution following the decimal point.
Example: 000.0000
3. Place the PTV into service mode for making
electronic adjustment, select the clock adjustment
DAC CLOCK and change value to 128.
4. Calculate and set
following formula:
= 128 +
CLOCK 0.450x106x
Note: Pin 10 measurement
regardless of the value stored in CLOCK.
Service Manual
signal from the RF
).
CLOCK based on the
{ ( ) Hz [ ] }
-
p in
732.422 Ð 10
----------------------------------------------------------- -
732.4220
will not change
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