Service Control Adjustments - Sanyo C28WP1 Service Manual

SERVICE CONTROL ADJUSTMENTS

Y-out ADJUSTMENT
1. Receive PAL colour bar pattern signal.
2. Connect a oscilloscope to "TP-Y"(+) and "TP-E"(-).
3. By using VR2801, adjust amplitude "A" to be 2.0
±0.05V.
AFT ADJUSTMENT
1. Receive the clearest station.
2. By using T121 (T141 is shown on top of the shield
case), adjust AFT to obtain the best picture.
AGC ADJUSTMENT
NOTE: Do not attempt this adjustment with weak
signal.
1. Receive the clearest station.
2. Set AGC VR(VR120) (VR131 is shown on top of the
shield case) in direction which causes snow noise to
appear, then in the opposite direction until snow noise
just disappears.
GREY SCALE ADJUSTMENT
[SCREEN VR ADJUSTMENT]
1. Receive white pattern signal.
2. Set brightness and contrast controls to maximum.
3. Set VR761 and VR781 to be mechanical centre.
4. Turn VR762, VR772 and VR782 fully counter-
clockwise.
5. Turn SW220 to "SERVICE" mode.
6. Set screen VR for one colour to be just visible.
[BIAS VR ADJUSTMENT]
7. By using VR762, VR772 or VR782, adjust line to be
white.
8. Turn SW220 to "NORMAL" mode.
[DRIVE VR ADJUSTMENT]
9. By using VR761 and VR781, adjust white balance.
F2JE
A
HIGH VOLTAGE CONFIRMATION
[HIGH VOLTAGE ADJUSTMENT]
1. Receive circular pattern signal.
2. Set brightness to centre and contrast to maximum.
3. Connect a high voltage meter to CRT anode.
4. Confirm high voltage to be 30.5 ± 1 KV, and less than
34.0KV at 0 beam current.
H-CENTRE ADJUSTMENT
1. Receive circular pattern signal.
2. Adjust H-centre by using VR371 (VR361 is shown on
top of the shield case).
V-CENTRE ADJUSTMENT
1. Receive circular pattern signal.
2. Adjust V-centre by using SW501.
FOCUS ADJUSTMENT
By using FOCUS VR, adjust focus control for well
scanning lines.
H-BLANKING ADJUSTMENT
NOTE: This must be done after picture size
adjustment.
1. Receive circular pattern signal.
2. Set screen mode to NORMAL.
3. Adjust right and left blanking width to be equal by
using VR1301(right) and VR1302(left).
DOLBY +B ADJUSTMENT
1. Connect a volt-meter to "TP-16V"(+) and"TP-16G"(-)
2. Adjust voltage to 12.0±0.1V by using VR1631
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