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Service Adjustments (Electronic Controls, cont.)
Clock Adjustment (S07)
Preparation:
Connect the frequency counter to TPS1 (IC001
pin-13) and cold ground (
).
Note: Frequency Counter probe capacitance should
be 8pF or less.
Procedure:
1.
Measure TPS1 (IC001 pin 13) for the frequency of
the waveform and record the reading.
Note: Pin 13 measurement must have at least four
digits of resolution following the decimal point.
Example: 000.0000
2.
Place the Receiver into Serviceman Mode for
making electronic adjustment, select the Clock
Adjustment DAC (S07).
3.
Calculate and set S07 based on the
following formula:
Note: Pin 13 measurement will not change
regardless of the value stored in S07.
Service Adjustments (Mechanical Controls)
Focus (part of T551)
This adjustment is to make the picture clear
Preparation:
Connect a Signal generator and select a dot pattern.
Procedure:
Adjust the FOCUS controls to obtain the sharpest and
clearest dot pattern.
a. Adjust VF1 to minimize width on vertical lines on
corners.
b. Adjust VF2 to minimize width on horizontal lines
on corners.
S07
128
873.90625
pin
13 Hz
[
]
–
{
}
968
+
=
Figure 38. Set Turned ON
S07
128
218.47656
pin
13 Hz
[
]
–
{
}
3873
+
=
Figure 39. Set Turned OFF
