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Service Manual
Note: Set the 30% modulation with the Pilot Light
and N.R. switches “OFF” then turn them “ON”
while testing.
5.
Adjust MTS High-Level Separation (S08) data
until
the amplitude of the waveform measured on the
scope is minimum.
6.
Repeat above steps 2 through 4 until the amplitude
is at minimum for both signals.
Clock Adjustment (S12)
Preparation:
Connect a frequency counter from IC001 MPU Pin
34 or TPA39, 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 IC001 MPU pin 34 for frequency and
record the reading.
Note: Pin 34 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 (S9) and change value to 128.
4.
Calculate and set S9 based on the
following formula:
Note: Pin 34 measurement will not change
regardless of the value stored in S09.
PIP Adjustment (TPY2)
Preparation:
1.
Apply a color bar pattern.
2.
Connect scope to connector A20 pin 2 on A-Board
or connector Y1 pin 2 (TPY2) on Y-Board.
3.
Turn PIP on.
Procedure:
1.
Adjust DAC P03 (PIP Contrast) until child
waveform level is 90% of parent waveform level.
See Fig. 12.
S
09
( )
128
1.35
x10
6
x
187.5000
pin
34
( )
Hz
[
]
–
{
}
187.5000
-------------------------------------------------------------------
+
=
C-Y
P-Y
Figure 12. Parent and Child Y
A
Ax0.9
WHITE
BLACK
Parent
Child
