Sharp 27J-S100 Service Manual page 12

27J-S100/180/260
CJ27S10/26
Ë Ë Ë Ë Ë adjustment
VCO Adjustment
1. Connect a digital voltmeter between pin 44 of IC201
and ground.
2. Select a good local channel.
3. Enter the service mode. select adjustment "S10".
4. Adjust the data so that digital voltmeter shold read
2.2V
5. Adjustment is complete, remove the volt-meter,
return to "normal" mode.
RF AGC Adjustment
1. Have unit receive a good local channel.
2. Enter the service mode and select service
adjustment "S 08".
3. Set the data value to point where no noise or beat
appears.
4. Select another channel to confirm that no noise or
beat appears.
NOTE1 :You will have to come out of the service
mode to select another channel.
NOTE2 :Setting the data to "0 0" will pro-duce a
black raster.
Screen adjustment
1. Connect a digital voltmeter between TP852 and
TP853 on the CRT socket PWB.
Note:These test points may not be provided.
Then connect the voltmeter to both ends of R852
located near Q851 on the foil side.
2. Select a good local channel.
3. Enter the service mode and select service
adjustment "S03" and set the data value to "00" to set
the color level to minimum.(Record original data code
under adjustment "S03" before changing) You may
skip this step if you selected a B/W picture or
monoscope pattern.
4. Select service adjustment "S19" and adjust the data
value to "01" this turn off the luminance signal (Y-
mute).
5. Select service adjustment "S04" and adjust data
value to obtain 0.26 volts on the digital voltmeter.
6. Adjust the master screen cotrol untill raster darkens
to the point where raster is barely seen.
7. Adjust service adjustments "S11" red,"S12" green
and "S13" blue to obtain a good grey scale with
normal whites at low brightness level.
8. Select service adjustment "S19" and reset data to
"00". Select service adjustment "S03" and reset data
to obtain normal color level.
9. Remove digital voltmeter.
Reset master screen cotrol to obtain normal
brightness range.
White balance adjustment
1. Have unit receive a good local channel.
2. Enter the service mode. select service adjustment "S
03" and set to "00" ( minimum color)(Record original
data code under adjustment "S03" before changing)
. "S 03" does not have to be adjusted if you selected
a B/W picture or monoscope pattern.
3. Alternately adjust service adjustment data of "S14"
and "S15" untill a good grey scale with normal whites
is obtained.
4. Select service adjustment "S 03"and adjust data to
obtain normal color level.
Sub-picture adjustment
1. Have unit receive a good local channel.
2. Make sure the customer picture control is set to
maximum.
3. Enter the service mode and select service
adjustment "S 01".
4. Adjust the data value to achieve normal contrast
range.
Sub-Tint Adjustment
1. Have unit receive a good local channel.
2. Set customer tint control to center of it's range.
3. Enter the service mode and select service
adjustment "S 02".
4. Adjust "S 02" data value to obtain normal flesh tones.
Sub-color adjustment
1. Have unit receive a good local channel.
2. Make sure the customer color control is set to center
position .
3. Enter the service mode and select service
adjustment "S 03".
4. Adjust "S 03"data value to obtain normal color level.
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