Repair Flow Chart (Continued)
V20 107E5
E. CPU
check list
check cpu pin6= 5V
pin9/pin8=12MhZ
pin7=gnd
power saving
pin27 pin22
normal
hi
hi
standby
low
hi
off
low
low
33,34,40,41
Hsync / Vsync
check sync.
Hsync_in=pin40
Vsync_in=pin41
Hsync_out=pin34
Vsync_out=pin33
Basic Check
check Q1-Q2
Pin36~38
low : 0
hi :1
36,37,38(Q3,Q2,Q1)
S-cap switch
1 . Normal
Fhout=Fhin
Fvout=Fvin
2. Self test
Hout=48Khz
Fvout=72Hz
3.sync out of rang
Fhin>72.8kHz,<28kHz
Fvin>168Hz, <45Hz
20, 27,22 P.S.
LED
18. Blanking
(mute)
check pin18
normal : low
change timing : Hi
H size compensation for
the load variance
31. H-EHT
pin 27 STBY
pin 22
OFF
check
from 5V to 0V
5, Reset
check
2801 / 3801
check
active=hi
no active=low
23. Degauss
70K S-CAPACITOR SWITCH TABLE
Hor. Freq.(KHz)
Q1
Q2
Q3
< 27.00
0
0
0
27.50-33.24
0
0
0
33.24-36.51
1
1
0
36.51-42.38
1
1
0
42.38-45.07
0
0
1
45.07-53.10
0
1
1
53.10-58.25
0
1
1
58.25-61.89
1
0
1
61.89-66.00
1
0
1
> 66.00
1
1
1
49
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