Sharp 29A-SX1, Service Manual

Page: 11 / 86

11
29A-SX1
29A-SX5
29A-SX8
SX-68JF200
11
SECAM CHR
OMA ADJUSTMENT
NO
.
Adjustment par
t
Adjusting procedure and conditions
W
a
v
e
fo
rm
and others
1
BELL FIL
TER f
o
I
2
C b
us adjust-
ment
1
Receiv
e Oi-5CH(SECAM colour bar).
2
Select the bell filter f
o
adjustment mode
.
3
Connect the oscilloscope to 21pin of IC900. Range :
10mV/Div
. (A
C)
Sw
eep time:
20
µ
sec/Div
. (10:1 probe is used.)
4
V
a
ry
the bell filter data to align the w
a
v
e
fo
rm
to
be the nearest to that in Fig. 1-1(b). (Arr
ange the le
v
el to gain the whole balance
.)
Fig. 1-1(a) Fig. 1-1(b)
1
Receiv
e Oi-5CH(SECAN colour bar).
2
Select SECAM b
lac
k le
v
el adjustment R-Y
mode
.
3
Connect the oscilloscope to 11pin of IC900 (R-
Y OUT
,
TP902).
Range:
10mV/Div
.
Sw
eep time:
20
µ
sec/Div
. (10:1 probe is used.)
4
V
a
ry
R-Y data to minimiz
e the offset betw
een
the non-signal line and signal line as sho
wn in
Fig. 2-1(b).
5
Select SECAM b
lac
k label adjustment B-Y
mode
.
6
Reconnect the oscilloscope to 10pin of IC900
(B-Y OUT
,
TP901).
The conditions are the same as in Item
3
.
7
V
a
ry
B-Y data to minimiz
e the offset betw
een
the non-signal line and signal line as sho
wn in
Fig. 2-2(b).
OFF SET
OFF SET
Fig. 2-1(a)
Fig. 2-1(b)
Fig. 2-2(a)
Fig. 2-2(b)
SECAM b
lac
k
le
v
el R-Y/B-Y
I 2
C b
us adjust-
ment
2