Electrical Adjustments - Toshiba MW27H62 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. Multi-sound Generator
4. Pattern Generator
On-Screen Display Adjustment
1. Set the VOLUME to minimum.
Press the VOL. DOWN button on the set and the
2.
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.
00 OSD H
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.
4. Press the MENU button on the remote control to end the
adjustments.
5. To display the adjustment screen for AV and YUV mode,
press the INPUT button on the remote control to set to
the AV and YUV. To display the adjustment screen for
DVD mode, press the DVD button on the remote control
to set to the DVD. Press the VOL.DOWN button on the
set and the channel (9) on the remote control for more
than 2 seconds.

ELECTRICAL ADJUSTMENTS

TV-A
4:3
1
Fig. 1-1
D3-1
NO. FUNCTION NO. FUNCTION
18
00 OSD H
19
01 OSD C
20
03 H.POSI
21
04 H.BLK L
22
05 H.BLK R
06 V.SIZE 23
07 V.POSI 24
25
08 V. LIN
26
09 VS.CORR
27
10 V.COMP
28
11 R.BIAS(M)
29
12 G.BIAS(M)
30
13 B.BIAS(M)
31
14 R.DRV(M)
32
15 G.DRV(M)
33
16 B.DRV(M)
34
17 R.BIAS(C)
2. BASIC ADJUSTMENTS
(VCR SECTION)
2-1: PG SHIFTER
1. Connect CH-1 on the oscilloscope to TP102 and CH-2 to
TP4201.
2. Playback the alignment tape.
3. Press both VOL. DOWN button on the set and the
Channel button (5) on the remote control for more than 2
seconds to set tracking to center.
4. Press the VOL. DOWN button on the set and the channel
button (3) on the remote control for more than 2 seconds
until the indicator REC disappears. If the indicator REC
disappears, adjustment is completed.
(If the above adjustments doesn't work well:)
5. Press the VOL. DOWN button on the set and the channel
button (3) on the remote control for more than 2 seconds
until the indicator REC disappears.
6. When the REC indicator is blinking, press both VOL.
DOWN button on the set and the channel button (4) on
the remote control for more than 2 seconds and adjust
the Tracking +/- button until the arising to the down of
Head Switching Pulse becomes 6.5 ± 0.5H.
(Refer to Fig. 2-1-A, B)
NO. FUNCTION
G.BIAS(C) 35 COL CENT
B.BIAS(C) 36 COL. MAX
R.DRV(C) 37 COL. MIN
G.DRV(C) 38 TINT
B.DRV(C) 39 SHARP.CENT
R.BIAS(W) 40 SHARP.MAX
G.BIAS(W) 41 SHARP.MIN
B.BIAS(W) 42 SUB BIAS
R.DRV(W) 43 H.SIZE
G.DRV(W) 44 PARABOLA
B.DRV(W) 45 TRAPEZIUM
BRI CENT 46 COR TOP
BRI MAX 47 COR BTM
BRI MIN 48 T.STE
CONT CENT
CONT MAX
CONT MIN
Fig. 1-2
CH-2
6.5H
CH-1
Fig. 2-1-A
CH-2
CH-1
6.5H
Fig. 2-1-B