Sharp 21C-FX1C, Руководство по обслуживанию

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10
21C-FX1(C)/(G) 21C-FX5/FX8
10-1 10-2
CUT-OFF, BACKGROUND AND SUB-CONTRAST ADJUSTMENT
No. Adjusting point Adjusting procedure/conditions Waveform and others
CRT CUTOFF
ADJUSTMENT 1. Switch TV to VIDEO mode,BLUE BACK OFF, with-
out VIDEO signal.
2. Press R/C to set Picture Normal condition.
3. First off the screen by adjust screen variable re-
sistor.
*4. Next, check AKB circuit function by slowly increase
screen variable resistor until colour raster suddenly
On and Off (AKB start function).
5. Then continue adjust unfil retrace line appear.
6. Finally, slowly decrease the screen variablu resis-
tor unfil screen retrace line (Not Raster) Cut Off.
*NOTE : Must comfirm the AKB function in set before
continue the next adjustment.
REMARK:
1. Before CRT Cutoff adjustment, SUB-BRIGHT, DRI-
RS/RC/RW, DRI-GS/GC/GW, DRI-BS/BC/BW,
CUT-R and CUT-G must be in initial data.
2. CRT Cutoff adjustment must be done inside a dark
room.
1
20mS
3.2 0.1 Vdc
0
SUB-BRIGHT-
NESS
ADJUSMENT
(I2C BUS
CONTROL) 1. Call " SUB-BRI" in service mode. (Receive Cross-
hatch pattern with 5 black level windows)
2. Adjust the " SUB BRIGHT " bus data in order that
the line 1 and 2 have the same darkness whereas
line 3 is one step (data) brighter than line 2 .Fi-
nally data minus 1 to make line 1,2 and 3 are in
same level darkness.
2
1 2 3 4 5
1
1 2 3 4 5
2
line 3 is one step (data) brighter
than line 2.
WHITE BAL-
ANCE SERV-
ICE MODE
ADJ. (I2C BUS
CONTROL) 1. Receive the "WHITE" pattern with BURST SIGNAL.
2. Press R/C to set Picture NORMAL condition.
3. Connect the DC miliammeter between the TP602
(-) TP603 (+).
4. Check Beam current should be around 1,350
µ
A.
5. Set it to service mode and adjust the " DRI-GS"
(White Point-G), "DRI-BS" (White Point-B) data
to have a colour temperature of 12,300
°
K or
18000ºK (white).
* Note .
6. Receive "White" pattern, with BURST signal, and
set Brightness Y by generator, to **10cd/m 2
(Minolta CA-100) by reducing Luminate Y signal.
7. Adjust "CUT-R" & "CUT-G" to get 12,300
°
K or
18000ºK . Then go back normal mode (High
Bright**) to check colour temperature. If out of
range, back to 5.
3 Refer to Page 7-2.
*18000
°
K X: 0.255
Y: 0.255
*12300
°
K X: 0.272
Y: 0.275
(MINOLTA COLOUR ANALYZER
CA-100)
*Note: Above Data can be UP/
DOWN by Volume key.
Low High
**Note: 10cd/m 2 180cd/m 2
*Alternative Procedure:
(1). Step (1),(2),(3) and (4) are same
as beside procedure.
(2). Then continue adjust until re-
trace appear and make sure the
colour appear wheather red,
green or blue
(3). Connect the oscilloscope to re-
lated test points as below which
is based on colour appear at (2)
Colour Appear Test Point
RED TP 851
GREEN TP 852
BLUE TP 853
(4). Then adjust SCREEN VR until
the tip of signal reach
3.2Vdc
±
0.1Vdc
HORIZONTAL AND VERTICAL DEFLECTION LOOP ADJUSTMENT
No. Adjusting point Adjusting procedure/conditions Waveform and others
V-LINEARITY
(I2C BUS
CONTROL)
V-CENTER
(I2C BUS
CONTROL)
V - AMP (I2C
BUS CON-
TROL)
H-CENTER
(I2C BUS
CONTROL)
S-CORREC-
TION
1. Receive Monoscope Pattern Signal.
2. Call the "V-LIN" mode.
3. Increase or decrease "V-LIN" by Volume key till
the horizontal line in the center of monoscope is
just at the position where the blanking starts.
1. Call the "V-CENT" mode.
2. Increase or decrease "V-CENT" by Volume key
till the picture is centered.
1. Call the "V-AMP" mode.
2. Increase or decrease "V - AMP" by Volume key
to set overscan of 8.5% typical.
Adjustment Spec 8.5% range +1% -1%.
1. Call the "H-CENT" mode.
2. Increase or decrease "H-CENT" by Volume key
to center the picture horizontal.
24(FIX DATA)
1
2
3
4
5
Maximum
beam check 1. Receive the "Monoscope Pattern" signal.
2. Press R/C to set Picture NORMAL condition.
3. Connect the DC miliammeter between TP603 (+)
and TP602 (–).
(Full Scale: 3 mA Range)
4. Beam current must be within 1,350
±
100
µ
A.
4
Note: This adjustment must be done after
warming up the unit for 30 minutes or
longer with a beam current over 700
µ
A).
* ADJUST DRI-GC/GW, DRI-BC/BW AS FOLLOW-
ING DATA, AFTER FINISHING DRI-GS AND DRI-
BS. *(12300ºK)
DRI-GC/GW DATA = “DRI-GS”-7 DATA
DRI-RC = 25; DRI-BC = DRI-BS; DRI-RW = 32
DRI-BW DATA = “DRI-BS”-7 DATA
*18000ºK
DRI-GW = "DRI-GS" DATA -7
DRI-BW = "DRI-BS" DATA -7
DRI-GC = "DRI-GS" DATA-5
DRI-RC = 27