Sharp 20D2-G, Service Manual

Page: 8 / 45

8
8-1
8-2
20D2-S/G
21D1-S/G
21D2-S/G
CONVERGENCE
ADJUSTMENT
No.
Adjusting point
Adjusting pr
ocedure/conditions
W
a
vef
orm and other
s
CONVERGENC ADJ
.
( T
o
be
done
after the purity adjustment.
1.
Receiv
e the
"Crosshatch
P
atter
n"
signal.
2
.
Using the remote controller
, call NORMAL mode
.
ST
A
TIC CONVERGENCE
1.
T
u
rn
the 4-pole magnet to a proper opening an-
gle in order to super
pose
the b
lue
and red col-
ours
.
2.
T
u
rn
the 6-pole magnet to a proper opening an-
gle in order to super
pose
the g
reen
colour o
v
er
the b
lue
and red colours
.
D
YNAMIC CONVERGENCE
1
.
Adjust the con
v
ergence
on the fr
inges
of the
screen in the f
ollo
wing
steps
.
a
)
Fig.
5-1:
Dr
iv
e
the w
edge
at point "a" and s
wing
the deflection coil upw
ard.
b)
Fig.
5-2:
Dr
iv
e the
w
edge at
points
"b"
and
"c"
and s
wing
the deflection coil do
wnw
ard.
c
)
Fig.
5-3:
Dr
iv
e the
"c"
w
edge deeper
and
swing
the deflection coil r
ightw
ard.
d
)
Fig.
5-4:
Dr
iv
e
the "b" w
edge
deeper and s
wing
the deflection coil leftw
ard.
2
.
Fix all the wedges on the CR
T and apply glass
tape o
v
er
them.
3
.
Apply lacquer to the deflection y
o
k
e
loc
k scre
w
,
magnet unit (pur
ity
, 4-pole
, 6-pole magnets) and
magnet unit loc
k scre
w
.
Finally receiv
ed
the Red-only and Blue-only sig-
nals to mak
e
sure there is no other colours on the
screen.
1
RGB BGR
R G B
R G B
B G R
B G R
RGB BGR
Lacquer
W
edge "a"
W
edge
"b"
W
edge
"c"
About 100
°
About 100
°
4-pole magnet
6-pole magnet
CR
T nec
k
20mm
21''
Lacquer
Pur
ity magnet
Fig.
5-1
Fig.
5-2
Fig.
5-3
Fig.
5-4
CR
T CUT
-OFF
, B
A
CKGR
OUND AND SUB-CONTRAST
ADJUSTMENT
No.
Adjusting point
Adjusting pr
ocedure/conditions
W
a
vef
orm and other
s
CR
T CUT
OFF
ADJUSTMENT (I
2
C B
U
S
CONTR
OL)
Remar
k
1
.
Bef
ore CR
T cutoff adjustment, SUB-BRIGHT
,
DRI-RS/R
W/RC
, DRI-GS/GW/GC
, DRI-BS/BW/
BC
, CUT
-R and CUT
-G m
ust be INITIAL D
A
T
A
.
2.
CR
T Cutoff adjustment m
ust be done inside a
dar
k room.
1
.
Switch
TV to
VIDEO mode
,BLUE BA
CK OFF
, with
NO VIDEO signal.
2.
Press R/C to set Picture Nor
mal
condition.
3.
First, off the screen b
y
adjust screen v
a
riab
le re-
sistor
.
*4.
Ne
xt, chec
king AKB circuit function b
y
slo
wly in-
crease screen v
a
riab
le
resistor until colour r
aster
suddenly on and off (AKB star
t function).
5.
Then contin
ue adjust until retr
ace line appear
.
6.
Finally
, slo
wly decrease the screen v
a
riab
le re-
sistor until screen retr
ace line cut off
. (Not Raster)
Note :
Must confir
m the AKB function in set bef
ore con-
tin
ue the
ne
xt
adjustment.
1
SUB-BRIGHT
-
NESS ADJUSMENT (I
2
C B
U
S
CONTR
OL)
1
.
Call " SUB-BRI" in ser
vice
mode
.
(Receiv
e
Cross-
hatch patter
n
with 5 b
lac
k
le
v
el
windo
ws)
2.
Adjust the " SUB BRIGHT " b
us data in order
that the line 1and 2 ha
v
e
the same dar
kness
wherelse line 3 is one step (data) br
ighter
than
line 2.
Finally data min
us
1 to mak
e
line 1, 2,
and 3 are in same le
v
el
(dar
kness).
2
Line 3 is one step (data) br
ighter than
line
2
t
3.2Vdc 0
WHITE B
AL-
ANCE SER
V
-
ICE MODE ADJ
. (I
2
C B
U
S
CONTR
OL)
1
.
Receiv
e the
"WHITE"
patter
n
with
B
URST
signal.
2.
Press R/C to set Picture NORMAL condition.
3
.
Connect the DC miliammeter betw
een
TP602
(-) TP603
(+).
4.
Chec
k Beam current should be around 1100
µ
A.
5.
Set it to ser
vice
mode and adjust the DRI-GS
,
&
DRI-BS data to ha
v
e
a colour temper
ature of
12300
°
K or 18000
°
K ( white ).
*Note
.
.
6.
Receiv
e "WHITE"
patter
n,
WITH
B
U
RST
signal,
and set BRIGHTNESS
Y b
y
gener
ator
, to **10
cd/m2 (MINOL
T
A
CA-100) b
y
reducing
LUMINA
TE Y
signal.
7.
Adjust "CUT
-R" & "CUT
-G" to get desired colour
temper
ature #.
Then go bac
k NORMAL mode
(HIGH BRIGHT**) to chec
k
colour temper
ature
.
If out of r
ange
, bac
k to (1).
Note:
This adjustment m
ust
be done after
warming up the unit f
or
30 min
utes
or
long
er with a beam current o
ver 700
µ
A.
* ADJUST DRI-GC/GW
, DRI-BC/BW AS FOLLO
W
-
ING D
A
T
A, AFTER FINISHING DRI-BS AND DRI-
GS D
A
T
A
ADJUSTMENT
.
DRI-R
W = 32 (FIXED), DRI-RS = 32 (FIXED)
DRI-BC = "DRI-BS" (F
or
12300
°
K
and
18000
°
K
Condition)
3
#
18000
°
K
X
: 0.255
Y
: 0.255
#
12300
°
K
X
: 0.272
Y
: 0.275
(MINOL
T
A
COLOUR ANAL
YZER
CA-100) *Note:
Abo
v
e
Data can be UP/
DO
WN b
y
V
olume k
e
y.
LO
W
HIGH
20"/21"
10cd/m2
120cd/m2
*Alter
nativ
e Procedure
(1) Step (1), (2), (3) and (4) are
same as beside procedure
.
(2) Then
contin
ue
adjust
until
re-
tr
ace
line appear and mak
e
sure
the colour appear whether red, green or b
lue
.
(3) Connect the oscilloscope to
related test points as belo
w
which is based on colour appear at (2) RED =
TP47R, GREEN =
TP47G, BLUE =
TP47B
.
(4)
Then adjust Screen
VR until the
tip of signal reach 3.2Vdc.
* 12300
°
K
DRI-BW="DRI-BS"-7 DRI-GW="DRI-BS"-7 DRI-GC="DRI-GS"-7 DRI-RC=25
* 18000
°
K
DRI-BW="DRI-BS"-7 DRI-GW="DRI-BS"-7 DRI-GC="DRI-GS"-5 DRI-RC=27
1 2
1 2 3 4 5 1 2 3 4 5
Ref
er to P
age 9-2.