ELECTRICAL ADJUSTMENTS
1. ADJUSTMENT PROCEDURE2. BASIC ADJUSTMENTS
Read and perform these adjustments when repairing the
circuits or replacing electrical parts or PCB assemblies.2-1: CONSTANT VOLTAGE
CAUTION1.Place the set with Aging Test for more than 5 minutes.
2.Set condition is AV MODE without signal.
YUse an isolation transformer when performing any service
3.Connect the digital voltmeter to the TP003.
on this chassis.
4.Adjust the VR502 until the digital voltmeter is 135 ? 0.5V.
YBefore removing the anode cap, discharge electricity
because it contains high voltage.
2-2: CUT OFF
YWhen removing a PCB or related component, after
unfastening or changing a wire, be sure to put the wire1.Place the set with Aging Test for more than 15 minutes.
back in its original position.2.Activate the adjustment mode display of Fig. 1-1 and
YWhen you exchange IC and Transistor for a heat sink,press the channel button (01) on the remote control to
apply the silicon grease on the contact section of the heatselect "CUT OFF".
sink. Before applying new silicon grease, remove all the3.Adjust the Screen Volume until a dim raster is obtained.
old silicon grease. (Old grease may cause damages to the
IC and Transistor.)2-3: WHITE BALANCE
Prepare the following measurement tools for electricalNOTE: Adjust after performing CUT OFF adjustment.
adjustments.
1.Place the set with Aging Test for more than 10 minutes.
1. Oscilloscope2.Receive the gray scale pattern from the Pattern Generator.
2. Digital Voltmeter3.Using the remote control, set the brightness and contrast
3. Multi-sound Generatorto normal position.
4. Pattern Generator4.Activate the adjustment mode display of Fig. 1-1 and
On-Screen Display Adjustmentpress the channel button (12) on the remote control to
select OR. BIAS�.
1. In the condition of NO indication on the screen.
5.Press the CH. UP/DOWN button on the remote control to
Press the VOL. DOWN button on the set and the Channel
select the OR. BIAS�, OG. BIAS�, OB. BIAS�, OB. DRIVE� or
button (9) on the remote control for more than 1 second to
OG. DRIVE�.
appear the adjustment mode on the screen as shown in
6.Adjust the VOL. UP/DOWN button on the remote control
Fig. 1-1.
to whiten the R. BIAS, G. BIAS, B. BIAS, B. DRIVE, and
G. DRIVE at each step tone sections equally.
TV7.Perform the above adjustments 5 and 6 until the white
color is looked like a white.
2-4: FOCUS
1.Receive the monoscope pattern.
00 OSD 302.Turn the Focus Volume fully counterclockwise once.
3.Adjust the Focus Volume until picture is distinct.
Fig. 1-1
2-5: HORIZONTAL PHASE
3.Use the Channel UP/DOWN button or Channel button
(0-9) on the remote control to select the options shown1.Receive the monoscope pattern.
2.Using the remote control, set the brightness and contrast
in Fig. 1-2.
to normal position.
4.Press the MENU button on the remote control to end the
3.Activate the adjustment mode display of Fig. 1-1 and
adjustments.
press the channel button (03) on the remote control to
NO. FUNCTIONNO. FUNCTIONselect OH. PHAS�.
00 OSD H19 CONTRAST CENT4.Press the VOL. UP/DOWN button on the remote control
01 CUT OFF20 CONTRAST MINuntil the SHIFT quantity of the OVER SCAN on right and
02 H. VCO21 COLOR MAX
03 H. PHASE22 COLOR CENTERleft becomes minimum.
04 AFC GAIN23 COLOR MIN
05 V. SHIFT24 TINT
06 H. SIZE25 SHARPNESS
07 V. SIZE26 Cb DELAY FINE
08 V. LINEARITY27 Cr DELAY FINE
09 VS CORRECTION28 Cb PEDESTAL ADJ
10 DRIVE R29 Cr PEDESTAL ADJ
11 DRIVE B30 E/W PARABOLA
12 R CUT OFF31 E/W CORNER
13 G CUT OFF32 E/W TRAPEZIUM
14 B CUT OFF33 LEVEL
15 BRIGHT MAX34 SEPARATION1
16 BRIGHT CENT35 SEPARATION2
17 BRIGHT MIN88 READ DATA
18 CONTRAST MAX
Fig. 1-2
D-1 |
ACEC
TOSHIBA
