Sharp 25WG3, Service Manual

Page: 8 / 44

8
25WG3
NO
ADJUSTMENT POINT
1
PURITY ADJ
.
1.
Receiv
e the GREEN -ONL
Y signal.
Adjust the beam current to ~800
µ
A.
2.
Or
ient the r
aster rotation to 0 eastw
ard.
3.
Degauss the CR
T enough with the
degausing coil.
4.
Maintain the purity magnet at the z
ero
magnetic field and k
eep the static
con
v
ergence roughly adjusted.
5.
Obser
v
e
the points a, b
, as sho
wn in
Fig.2-1 through the microscope
. Adjust
the landings to A r
ank requirement.
6.
Tighten up the deflection coil scre
ws
.
Tightening torque : 108N
±
20N
(11Kgf
±
2Kgf)
7.
Mak
e sure the CR
T cor
ners landing
meet the A r
ank requirements
. If not,
stic
k the magnet sheet to correct it.
Note:
This adjustment m
ust be done
after w
a
rming up the unit f
or 30
min
utes or longer with a beam
current o
v
er 1000
µ
A.
Note:
Set the ser
vice mode b
y
ser
vice
s
witch ( S 1006) then press
factor
y process R/C RGB k
e
y to
change to g
reen only
.
* F
or the f
ollo
wing colour press colour k
e
y
to change
.
ADJUSTMENT CONDITION/PROCEDURE
PURITY ADJUSTMENT
Figure 2-1
WAVEFORM OR OTHERS
Figure 2-2
Rank A (On the right of CR
T)
Figure 2-3
Rank A (On the left of CRT)
T
e
xt K
e
y "R.G.Cy" K
e
y
can be directly use to change to other colours screen.
1.
Receiv
e the "CR
OSSHA
TCH
P
A
TTERN" signal.
2.
Using the remote controller
, call
NORMAL mode
.
(Static con
v
ergence)
1.
T
u
rn
the 4 - pole magnet to a proper
opening angle in order to super
pose the
b
lue and red colours
.
2.
T
u
rn
the 6 - pole magnet to a proper
opening angle in order to super
pose the
g
reen colour o
v
er the b
lue and red
colours
.
(Dynamic con
v
ergence)
1.
Adjust the con
v
ergence on the fr
inges of
the screen in the f
ollo
wing steps
.
a) Fig. a :
D
ri
v
e
the w
edge at point "a"
and s
wing the deflection coil
upw
ard.
b) Fig. b :
D
ri
v
e
the w
edge at point "a"
and "b" and s
wing the
deflection coil do
wnw
ard.
c) Fig. c :
D
ri
v
e
the "c" w
edge deeper
and s
wing the deflection coil
rightw
ard.
d) Fig. d :
D
ri
v
e
the "b" w
edge deeper
and s
wing the deflection coil
leftw
ard.
2.
Fix all the w
edges 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 ( purity 4 - pole
, 6 -
pole magnets ) and magnet unit loc
k
scre
w
.
Finally receiv
ed the Red - only and Blue
- only signals to mak
e sure there is no
other colours on the screen.
Figure 4
4-pole Magnet
6-pole Magnet
CRT NECK
Lacquer
Purity Magnet NECK
R
R
G
G
B
B
Figure a Figure b
BG
R
B G R
RG
B
B
G
R
Figure c
BG
R
R
G
B
Figure d
CONVERGENCE ADJUSTMENT
NO
ADJUSTMENT POINT
1
CONVERGENCE ADJ
.
(T
o be done after the
purity adjustment.)
ADJUSTMENT CONDITION/PROCEDURE
WAVEFORM OR OTHERS
Wedge "a"
Wedge "b"
Lacquer
Wedge "c"
About 100˚
About 100˚
Figure 3