Sharp 14VT10X1, Service Manual

Page: 35 / 138

ADJUSTMENT OF Y/C CIRCUIT
l Test point layout
Figure PWB
n
ADJUSTMENT OF Y/C CIRCUIT
Adjustment of EE level
Measuring
instrument
Oscilloscope
Mode
Recording
Input signal
Standard colour bar
(stair-case waveform)
Test point
Pin of (video output)
Adjusting point
R202 (EE level control)
Specification
2.0 (not terminated)
1. Set the unit in record mode.
2. Feed the colour bar signal to the video input
terminal. Observe the voltage of pin of
on the oscilloscope screen, adjust R202 (EE level
control) to obtain the value indicated in Figure 2-
5.
Adjustment of white clip
Measuring
instrument
Oscilloscope
Mode
Input signal
Recording
Standard colour bar
(stair-case waveform)
Test point TP201
Adjusting point
R232 (white clip control)
Specification
1.
2.
3.
4.
5.
Place the unit to the record mode.
Feed the colour bar signal to the video input
terminal
.
Turn R227 clockwise to maximum position.
Observing the output at
adjust R232
(white clip control) so that the white peak
overshoot be 80 4%.
Make sure that the dark peak overshoot is 50
10%.
DARK
CLIP
50%
Figure 2-5.
Figure 2-6.
37