ELECTRICAL ADJUSTMENTS
D-1
20AF45/20AF45C
FUNCTION
CONTRAST MAX
CONTRAST CENT
CONTRAST MIN
COLOR MAX
COLOR CENTER
COLOR MIN
TINT
SHARPNESS
CB DL
CR DL
CB PED
CR PED
PARABOLA
CORNER
TRAPWZIUM
LEVEL
SEPARATION1
SEPARATION2
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 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 29
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.
FUNCTION
OSD H
CUT OFF
H. VCO
H. PHASE
AFC GAIN
V. SHIFT
H. SIZE
V. SIZE
V. LINERITY
VS CORRECTION
R DRIVE
B DRIVE
R BIAS
G BIAS
B BIAS
BRIGHT MAX
BRIGHT CENT
BRIGHT MIN
NO.
00
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
Fig. 1-2
NO.
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
2. BASIC ADJUSTMENTS
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 113
±
0.5V.
•
•
•
•
2-2: CUT OFF
1.
2.
3.
4.
5.
Place the set in Aging Test for more than 15 minutes.
Set condition is 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.
2-3: WHITE BALANCE, WHITE BALANCE CS
NOTE: Adjust after performing CUT OFF adjustment.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
Place the set in Aging Test for more than 15 minutes.
Receive the gray scale pattern from the Pattern Generator
with Brust On.
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 (12) on the remote control to
select “R. BIAS”.
Press the CH. UP/DOWN button on the remote control to
select the “R. BIAS”, “G. BIAS”, “B. BIAS”, “B. DRIVE” or
“R. DRIVE”.
Adjust the VOL. UP/DOWN button on the remote control
to whiten the R. BIAS, G. BIAS, B. BIAS, B. DRIVE and
R. DRIVE at each step tone sections equally.
Perform the above adjustments 5 and 6 until the white
color is looked like a white.
Press the TV/VIDEO button on the remote control to set
to the CS mode.
Receive the gray scale pattern from the Pattern Generat
or with Brust On.
If the picture is too much green.Activate the adjustment
mode display of Fig. 1-1 and press the channel button
(28) on the remote control to select “CB PED”.
Adjust the VOL. UP/DOWN button on the remote control
to select the step up.
If the picture is too much red.Activate the adjustment mode
display of Fig. 1-1 and press the channel button
(29) on the remote control to select “CR PED”.
Adjust the VOL. UP/DOWN button on the remote control
to select the step down.
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.
