Toshiba 27D46 - Adjustment Procedure; Basic Adjustments; Electrical Adjustments

ELECTRICAL ADJUSTMENTS
D-1
1. ADJUSTMENT PROCEDURE
Read and perform these adjustments when repairing the
circuits or replacing electrical parts or PCB assemblies.
2. BASIC ADJUSTMENTS
Prepare the following measurement tools for electrical
adjustments.
1. Oscilloscope
2. Digital Voltmeter
3. Multi-sound Generator
4. Pattern Generator
On-Screen Display Adjustment
1. In the condition of NO indication on the screen.
Press the VOL. DOWN button on the set and the Channel
button (9) on the remote control for more than 2 seconds
to appear the adjustment mode on the screen as shown in
Fig. 1-1.
Fig. 1-1
2.
3.
4.
Use the Channel UP/DOWN button or Channel button
(0-9) on the remote control to select the options shown
in Fig. 1-2.
Press the MENU button on the remote control to end the
adjustments.
To display the adjustment screen for AV, CS and
DIGITAL mode, press the TV/VIDEO button on the
remote control to set to the AV, CS and DIGITAL mode.
Press the VOL.DOWN button on the set and the
channel (9) on the remote control for more than 2
seconds.
TV-A
00 OSD H
Fig. 1-2
FUNCTION
OSD H
OSD C
CUT OFF
H.POSI
H BLK L
H BLK R
V. SIZE
V POSI
V.LIN
VS CORR
V COMP
R.BIAS
G.BIAS
B.BIAS
R.DRV
G.DRV
B.DRV
BRI.CENT
BRI.MAX
BRI.MIN
NO.
00
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
NO.
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
FUNCTION
CONT.CENT
CONT.MAX
CONT.MIN
COL.CENT
COL.MAX
COL.MIN
TINT CENT
SHARP.CENT
SHARP.MAX
SHARP.MIN
SUB BIAS
H.SIZE
PARABOLA
TRAPEZIUM
COR TOP
COR BTM
TEST STEREO
TEST AUDIO
H FREQ
4:3
0
CAUTION
Use an isolation transformer when performing any
service on this chassis.
Before removing the anode cap, discharge electricity
because it contains high voltage.
When removing a PCB or related component, after
unfastening or changing a wire, be sure to put the wire
back in its original position.
When you exchange IC and Transistor with a heat sink,
apply silicon grease on the contact section of the heat
sink. Before applying new silicon grease (YG6260M) ,
remove all the old silicon grease. (Old grease may
cause damages to the IC and Transistor.)
2-3: FOCUS
1.
2.
3.
Receive the monoscope pattern.
Turn the Focus Volume fully counterclockwise once.
Adjust the Focus Volume until picture is distinct.
2-1: CONSTANT VOLTAGE
1.
2.
3.
Place the set in AV MODE without signal.
Connect the digital voltmeter to the TP003.
Adjust the VR502 until the digital voltmeter is 120 ± 0.5V.
2-2: CUT OFF
1.
2.
3.
4.
5.
Place the set in Aging Test for more than 15 minutes.
Place the set in AV MODE without signal.
Using the remote control, set the brightness and
contrast to normal position.
Activate the adjustment mode display of Fig. 1-1 and
press the channel button (02) on the remote control to
select "CUT OFF".
Adjust the Screen Volume until a dim raster is obtained.
2-4: WHITE BALANCE
NOTE: Adjust after performing CUT OFF adjustment.
Place the set in Aging Test for more than 15 minutes.
Receive the white 100% signal from the Pattern
Generator.
Using the adjustment control, set the brightness and
contrast to normal position.
Activate the adjustment mode display of Fig. 1-1 and
press the channel button (11) on the remote control to
select "R.BIAS".
Using the VOL. UP/DOWN button on the remote control,
adjust the R.BIAS.
Press the CH. UP/DOWN button on the remote control to
select the "R.DRIVE", "B.DRIVE", "G.BIAS" or "B.BIAS".
Using the VOL. UP/DOWN button on the remote control,
adjust the R.DRIVE, B.DRIVE, G.BIAS or B.BIAS.
Perform the above adjustments 6 and 7 until the white
color is achieved.
1.
2.
3.
4.
5.
6.
7.
8.
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