Sanyo 28H1, Service Manual

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Service Manual EH1 chassis
[OUTPUT LEVEL ADJUSTMENT-R-Y]
1. Connect oscilloscope between pin 10 of K73C(+) and
GND(-).
2. Adjust the R-Y signal amplitude to be 0.7Vp-p by using
VR7352.
[OUTPUT LEVEL ADJUSTMENT-B-Y]
1. Connect oscilloscope between pin 8 of K73C(+) and
GND(-).
2. Adjust the B-Y signal amplitude to be 0.7Vp-p by using
VR7353.
SCREEN ADJUSTMENT
1. Receive the PAL colour bar pattern.
2. Connect oscilloscope between ) and
JTP47E(-) on the CRT unit.
3. Adjust colour control to minimum, brightness to centre
and contrast to minimum.
4. Adjust the black level to be 165V
DC
±5V by using
SCREEN VR on the FBT.
HIGH VOLTAGE CONFIRMATION
1. Receive the white pattern.
2. Set brightness and contrast controls to maximum.
3. Connect digital V-meter between “TP451” and
“TP452”, and high voltage meter to CRT anode.
4. Confirm high voltage to be 28.5 ± 1 KV at beam
current 1.8, and less than 32.5 KV at 0 beam current.
FOCUS ADJUSTMENT
By using FOCUS VR, adjust focus control for well
defined scanning lines.
165V
DC
DC=0
Black level
0.7Vp-p
0.7Vp-p