Electrical Adjustments; Basic Adjustments - Toshiba MD14F52 Service Manual

1. BEFORE MAKING ELECTRICAL
ADJUSTMENTS
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. Before 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. AC Voltmeter
4. Pattern Generator
5. Multi-Sound Signal Generator
On-Screen Display Adjustment
1. Set the VOLUME to minimum.
2. 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.
Function
01 OSD
Step No.
3. Use the Channel UP/DOWN button or Channel button
(1-0) on the remote control to select the options shown
in Fig. 1-2.
4. Press the MENU button on the remote control to end the
adjustments.
ELECTRICAL ADJUSTMENTS
17
Fig. 1-1
NO. FUNCTION
01 OSD
02 CUT OFF
03 HVCO
04 HPHA
05 VSIZ
06 VSHI
07 RDRV
08 BDRV
09 RCUT
10 GCUT
11 BCUT
12 BRTC
13 BRTX
14 BRTN
15 CNTC
16 CNTX
17 CNTN
18 COLC
19 COLX
20 COLN
21 TNTC
22 SHRP
23 BRTCA
24 BRTXA
25 BRTNA
26 CNTCA
27 CNTXA

2. BASIC ADJUSTMENTS

2-1: CONSTANT VOLTAGE
1. Place the set in AV MODE without signal.
2. Using the remote control, set the brightness and contrast
to normal position.
3. Connect the digital voltmeter to TP401.
Adjust the VR3800 until the digital voltmeter is 115 ± 1V.
4.
2-2: FOCUS
1. Receive the monoscope pattern.
2. Turn the Focus Volume fully counterclockwise once.
3. Adjust the Focus Volume until picture is distinct.
2-3: CUT OFF
1. Adjust the unit to the following settings.
R CUT OFF=7F, G CUT OFF=7F, B CUT OFF=7F,
R DRIVE=3F, B DRIVE=3F
2. Set condition is Aging Test for more than 15 minutes.
3. Set condition is AV MODE without signal.
4. Using the remote control, set the brightness and
contrast to normal position.
5. Activate the adjustment mode display of Fig. 1-1 and
press the channel button (02) on the remote control to
select "CUT OFF".
6. Adjust the Screen Volume until a dim raster is obtained.
D-1
NO FUNCTION
.
28 CNTNA
29 COLCA
30 COLXA
31 COLNA
32 TNTCA
33 SHRPA
34 BRTCD
35 BRTXD
36 BRTND
37 CNTCD
38 CNTXD
39 CNTND
40 COLCE
41 COLXD
42 COLND
43 TNTCD
44 SHRPD
45 BRTCG
46 BRTXG
47 BRTNG
48 CNTCG
49 CNTXG
50 CNTNG
51 TVM
52 PVM
53 LVL
54 SEPAL
Fig. 1-2
55 SEPAH