Sharp 21L-FG1RU, Service Manual

Page: 21 / 80

21L-FG1SA/SF/SM/RU
3 – 18
4. H-VCO, VIF-VCO & S-TRAP fo ADJUSTMENT
No. Adjustment point Adjustment procedure/conditions Waveform and others
H-VCO ADJ
(I
2
C BUS
CONTROL)
(AUTO &
MANUAL ADJ)
(MANUAL ADJ)
1) In No signal (RASTER) condition.
2) Go to service mode, choose service data
V03 .
3) Connect oscilloscope to IC801 pin15 , adj V03 until
freq become 15.625
±
0.15 KHz
(Auto Adj)
1) In No signal (RASTER) condition.
2) Go to service mode.
3) Choose service data
V03 , by pressing R/C Auto
(Hex C1) key, OSD will appear “OK” at screen.
4) If appear “NG” pls repeat step 3.
(Manual ADJ)
1) In No signal (RASTER) condition.
2) Go to service mode, choose service data
V02 .
3) Connect oscilloscope to IC801 pin9 , adj V02 until
voltage become 2.5
±
1 V .
(Auto Adj)
1) In No signal (RASTER) condition.
2) Go to service mode, choose service data
V02.
3) Press the R/C Auto (Hex C1) key, OSD will appear
“OK” at screen.
4) If appear “NG” pls repeat step 3.
(Manual ADJ)
1) In No signal (RASTER) condition.
2) Go to service mode, choose service data
V21 .
3) Connect oscilloscope to TP 801, adj V21 until
voltage become Min (below 5 V).
4) After that pls adj service data V20 & V24 same as
“V21”, V22 to “V21-1”, V23 to “V21+2” .
(Auto Adj)
1) In No signal (RASTER) condition.
2) Go to service mode, choose service data
V21 .
3) Press the R/C Auto (Hex C1) key, OSD will appear
“OK” at screen.
4) If appear “NG” pls repeat step 3.
1
VIF-VCO ADJ
(I
2 C BUS
CONTROL)
(AUTO &
MANUAL ADJ)
2
S-TRAP fo
ADJ
(I
2 C BUS
CONTROL)
(AUTO &
MANUAL ADJ)
3
This adjustment must be done
after aging at least 3 minutes.