Sharp 29K-FD5RU, Руководство по обслуживанию

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12
29K-FD5RU 29K-FG5RU
12-1 12-2
PURITY ADJUSTMENT
No. Adjustment point Adjustment conditions/procedure Waveform or remarks
PURITY ADJ. 1. Select the green monocolor screen with remote
contoller, and set the beam current of 1.7mA
with the contrast control.
2. Degauss the CRT enough with the degausing coil.
Note: Follow the job instruction manual to
adjust the magnetic field.
.
3. The purity magnet must be previously set at the
0 magnetic field, and the convergence must be
adjusted to be rough.
With P-MAG, adjust it to the center - rank A.
4. Observe the points a,b, as shown in Fig.1-1
through the microscope.
Move DY fore and aft to set the landing at the
point (Rank A).
5. If the a/b balance is poor, compensate it to the
center "Rank AB".
6. Aline it to zero, keeping the raster rotation in the
east direction.
6. Tighten the deflection coil fastening screws.
»
Tightening torque : 108N
±
20N (11Kgf
±
2Kgf)
8. Checking the CRT corner area, bond the mag-
netic sheet to set the landing at rank A for com-
pensation.
Note: Apply the adjustment after aging with
the beam current 1700
±
50
µ
A or more
for 30 minutes or more.
Note: Select the service mode, and press the
monocolor key of R/C for process, and
the monocolor screen (green) will be
selected.
1
a
b
A
B
A
90mm 90mm
B
A = B
A = B
Fig.1-1
Fig. 1-2
Rank "A"
(on the right of the CRT)
Fig. 1-3
Rank "A"
(on the left of the CRT)
* Continuosly press the mono-
colour key 1 second or more,
and the monocolour mode will
be selected without the service
mode.
*Even with TEXT key or "R/G/B"
key, it can be directly switched to
each monocolor screen.
Monocolour
screen release
Monocolour
GREEN
screen
Monocolour
BLUE
screen
Monocolour
RED
screen
* Adjustment for uniformity is change to another
content. Please refer to the following page.
* Every push of the monocolour key changes the
screen as follows.
PURITY ADJUSTMENT
No. Adjustment point Adjustment conditions/procedure Waveform or remarks
Uniformity
adjustment (To
perform after
the purity and
convergence
adjustment.) 2 Before adjustment begin,Horizontal magnetic field
= 0G
Vertical magnetic field = Each destination's adjust-
ment magnetic field.
Make sure to degauss it.
(North direction Red uniformity)
1. Horizontal mf = Set to monocolor screen red and
adjust to +0.25G.
2. Pay attention to the edge of CRT,if the landing is
poor adjust by attaching the the compensation
magnet at the back of CRT.
(refer to Fig-1)
(South direction Red uniformity)
1. Horizontal mf = Set to monocolor screen red and
adjust to -0.25G.
2. Pay attention to the edge of CRT ,if the landing is
poor adjust by attaching the compensation mag-
net at the back of CRT.
(The same method is applied for adjustment of
monocolor screen blue for blue uniformity ,and
changing both the magnetic field for north and south
direction.)
* During the pasting of compensation magnet , use
the crosshatch pattern .
Make sure there is no blur or bendlines occur.
If the blur or bend are serious,adjust the location
of compensation magnet to make it better.
(CRT surface)
(CRT back)
Miss landing
Compensation magnet
Fig. 1