ELECTRICAL ADJUSTMENTS
1. ADJUSTMENT PROCEDURE2. BASIC ADJUSTMENTS
Read and perform these adjustments when repairing the
2-1: CONSTANT VOLTAGE
circuits or replacing electrical parts or PCB assemblies.
1.Place the set with Aging Test for more than 15 minutes.
CAUTION
2.Place the set in AV MODE without signal.
Y Use an isolation transformer when performing any3.Using the remote control, set the brightness and contrast
service on this chassis.to normal position.
Y Before removing the anode cap, discharge electricity4.Connect the digital voltmeter to R521.
because it contains high voltage.5.Adjust the VR501 until the digital voltmeter is 117 ? 1V.
Y When removing a PCB or related component, after
unfastening or changing a wire, be sure to put the wire2-2: DCXO AUTO
back in its original position.
1.Receive the cross hatch signal from the Pattern
Y When you exchange IC and Transistor with a heat sink,
Generator.
apply silicon grease (YG6260M) on the contact section
2.Activate the adjustment mode display of Fig. 1-1 and
of the heat sink. Before applying new silicon grease,
press the channel button (002) on the remote control to
remove all the old silicon grease. (Old grease may
select "DCXO AUTO".
cause damages to the IC and Transistor.)
3.Press the VOL. UP/DOWN button on the remote control
Prepare the following measurement tools for electricaluntil the DCXO AUTO step changed from "1" to "0".
adjustments.
2-3: AGC VOLTAGE
1. Oscilloscope
2. Digital Voltmeter1.Place the set with Aging Test for more than 15 minutes.
3. Multi-sound Generator2.Receive the UHF (63dB).
4. Pattern Generator3.Connect the digital voltmeter to the pin 5 of CP101.
4.Activate the adjustment mode display of Fig. 1-1 and
On-Screen Display Adjustment
press the channel button (036) on the remote control to
1. In the condition of NO indication on the screen.select "AGC TAKE OVER".
Press the VOL. DOWN button on the set and the5.Press the VOL. UP/DOWN button on the remote control
Channel button (9) on the remote control for more than 2until the digital voltmeter is 2.40 ? 0.05V.
seconds to appear the adjustment mode on the screen
as shown in Fig. 1-1.2-4: CUT OFF
1.Place the set in Aging Test for more than 15 minutes.
2.Place the set in AV MODE without signal.
3.Using the remote control, set the brightness and
contrast to normal position.
4.Activate the adjustment mode display of Fig. 1-1 and
press the channel button (003) on the remote control to
select "CUT OFF".
Crystal alignmen
001 DCXO 475.Adjust the Screen Volume until a dim raster is obtained.
Fig. 1-12-5: WHITE BALANCE
NOTE: Adjust after performing CUT OFF adjustment.
2.Use the Channel UP/DOWN button or Channel button
(0-9) on the remote control to select the options shown1.Place the set in Aging Test for more than 15 minutes.
in Fig. 1-2.2.Receive the gray scale pattern from the Pattern
3.Press the MENU button on the remote control to end theGenerator.
adjustments.3.Using the remote control, set the brightness and
contrast to normal position.
NO. FUNCTIONNO. FUNCTION
4.Activate the adjustment mode display of Fig. 1-1 and
001 DCXO021WPR-N
002 DCXO Auto022 WPG-Npress the channel button (021) on the remote control to
003 CUT OFF023 WPB-N
select "WPR-N".
004 VG2024RGB
005 Vertical, Slope025 PT-BR-SP CENTER5.Press the Page UP/DOWN button on the remote
006 Vert, Shift026 PT-BR-SP MAX
control to select the "WPR-N", "WPG-N", "BLOR-N" or
007 Vert, Ampl.027PT-BR-SP MIN
008 S-Corr.028 PT-CL-SP CENTER"BLOG-N".
009 V.Lin.Ctrl.029 PT-CL-SP MAX
6.Adjust the VOL. UP/DOWN button on the remote control
010 V.Linearity030PT-CL-SP MIN
011 Hor,Shift031 PT-CT-SP CENTERto whiten the WPR-N, WPG-N, BLOR-N, and
012 EW Width032 PT-CT-SP MAX
BLOG-N at each step tone sections equally.
013 EW Parabola033PT-CT-SP MIN
014 Trapezium034 PT-SH-SP7.Perform the above adjustments 5 and 6 until the white
015 UC Parabola035 Tint det
color is achieved.
016 LC Parabola036AGC TAKE OVER
017 Parallelogram037OSD VPOS
018 Hor.Bow038OSD HPOS
019 BLOR-N039TXT VPOS
020 BLOG-N040TXT-H-POS
Fig. 1-2
D-1 |
ACEC
TOSHIBA
