Sharp 21F-PA330I, Руководство по обслуживанию

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ADJUSTMENT PRECAUTION:
Make sure TV Set is in “Normal Condition” before witch to service mode for adjustment.
PIF ADJUSTMENT
No.
1
2
Adjusting point
Tuner IFT
(PRESET)
RF-AGC
TAKE OVER
POINT
ADJUSTMENT
(I2C BUS
CONTROL)
(AUTO &
MANUAL ADJ)
Get the tuner ready to receive the CH. - 9
signal, but with no signal input.
Adjust the PLL data.
Connect the sweep genertor’s output cable to
the tuner antenna. (RF SWEEP)
Adjust the sweep genertor’s to 80dB
µ
V.
Connect the response lead (use LOW IMPEDANCE
probe with wave detector. (This terminal must
have the probe alone connected).
Set the RF AGC to 0 - 6 V with no saturation with
the waveform.
Adjust the tuner IF coil to obtain the wavefrom as
show in Fig. 2.
NOTE: Be sure to keep the tuner cover in posi-
tion during this adjustment.
Receive “PAL COLOUR BAR” signal.
Signal Strength: 56 1 dB
µ
V (75 ohm open)
Connect the oscilloscope to TP201 (Tuner’s
AGCTerminal) as show in Fig. 3.
Call “V01” mode in service mode. Adjust the “V01”
bus data to obtain the Tuner output pin drop
0.1~1.0V below maximum voltage.
Change the antenna input signal to 63~67dB
µ
V,
and make sure there is no noise.
Turn up the input signal to 90~95 dB
µ
V to be sure
that there is no cross modulation beat.
Wavefrom and others
for Auto ADJ
Receive “PAL COLOUR BAR”
signal.
Signal strength : 56 1 dB
µ
V (75
ohm open)
Go to service mode.
Go to service data V01, press
R/C to operate auto key (Hex
C1) and confirm the ‘OK’
display on the screen.
If appear NG, increase data
some step and pis repeat
step2.
Preceed step 4&5 in manual
mode.
PURITY ADJUSTMENT
No.
1
Adjusting point
PURITY ADJ.
Receive the GREEN-ONLY signal. Adjust the
beam current to ~700
µ
A.
Degauss the CRT enough with the degauss coil.
Note: Follow the Job Instruction Sheet to adjust
the magnetic field.
Vertical Bv: +0.030 mT (0.30 gauss)
Horizontal Bh: +0.20 mT (0.20 gauss)
Maintain the purity magnet at the zero magnetic
field and keep the static convergence roughly
adjusted.
Observe the points a, b, as show in Fig. 1-1
through the microscope. Adjust the landings to A
rank requirement.
Orient the raster rotation to 0 eastward.
Tighten up the deflection coil screws.
Tightening torque: 108 20 N (11 2 kgf)
Make sure the CRT corners landing meet the A rank
requirements. If not, stick the magnet sheet
to correct it.
Note: This adjustment must be done after
warming up the unit for 30 minutes or
longer with a beam current over 700
µµµµµ
A.
Note: Set to service mode by remote con-
troller then press factory process R/C
RGB key to change to RGB mono col-
our mode.
* For the following colour press R/C RGB(Hex 7E)
key to change.
Wavefrom and others
* Press R/C RGB key for 1 sec-
ond in NORMAL MODE, the
colour will change to RGB
mono colour mode.
Signal-colour
screen cleared
GREEN
ONLY
BLUE
ONLY
RED
ONLY
E-9 CH
P C
-1.5+/-0.8dB
10k
100k
1n60
75ohm
IF OUT
1000p
1000p
Oscilloscope
Fig. 2
Fig. 1
1.
2.
3.
4.
5
6.
Adjusting procedure/conditions
1.
2.
3.
4.
5
Bias box: About 4.5 V
Oscilloscope
0.1V
TV Set Bias box
TP201 +
+
—
—
Fig. 3
1.
2.
3.
4.
1.
2.
3.
4.
5
6.
7.
Adjusting procedure/conditions
a
b
30mm 30mm
A
B
A = 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)
8
8-2
8-1
+_
+_
+_
+_