ELECTRICAL ADJUSTMENTS
1. ADJUSTMENT PROCEDURE
Read and perform these adjustments when repairing the
circuits or replacing electrical parts or PCB assemblies.
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 (YG6260M) on the contact section
of the heat sink. Befor applying new silicon grease,
remove all the old silicon grease. (Old grease may
cause damages to the IC and Transistor.)
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
TV
00 OSD 17
2.
3.
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.
2. BASIC ADJUSTMENTS
2-1: CONSTANT VOLTAGE
1.
2.
3.
Place the set in AV MODE without signal.
Connect the digital voltmeter to the TP401.
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 (01) on the remote control to
select “CUT OFF”.
Adjust the Screen Volume until a dim raster is obtained.
FUNCTION
OSD H
CUT OFF
H.VCO
H.PHASE
V.SIZE
V.SHIFT
R.DRIVE
B.DRIVE
R.BIAS
G.BIAS
B.BIAS
BRIGHT CENT
BRIGHT MAX
BRIGHT MIN
NO.
00
01
04
05
06
07
08
09
10
11
12
13
14
15
Fig. 1-2
FUNCTION
CONTRAST CENT
CONTRAST MAX
CONTRAST MIN
COLOR CENT
COLOR MAX
COLOR MIN
TINT
SHARPNESS
FM LEVEL
LEVEL
SEPARATION 1
SEPARATION 2
TEST MONO
TEST STEREO
NO.
16
17
18
19
20
21
22
23
24
25
26
27
28
29
2-3: 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 (10) 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.
2-4: FOCUS
1.
2.
3.
Receive the monoscope pattern.
Turn the Focus Volume fully counterclockwise once.
Adjust the Focus Volume until picture is distinct.
2-5: VERTICAL POSITION
1.
2.
3.
Receive the monoscope pattern.
Using the remote control, set the brightness and contrast
to normal position.
Adjust the VR401 until the horizontal line becomes fit to
the notch of the shadow mask.
(Refer to Fig. 2-1)
Fig. 2-1
Shadow mask
Notch
horizontal line
,,
,,
,,
,,
,,
,,
,,
,
D-1