Toshiba 20A42, Service Manual

Page: 14 / 35

ELECTRICAL ADJUSTMENTS
Activate the adjustment mode display of Fig. 1-1 and
press the channel button (17) on the remote control to
select "CONT.MAX".
Press the VOL. UP/DOWN button on the remote control
until the contrast step No. becomes "65".
Receive a broadcast and check if the picture is normal.
Press the TV/VIDEO button on the remote to set to the
AV mode. Then perform the above adjustment 1~3. 1.
2.
3.
4.
2-14: SUB CONTRAST
Please check if the fixed values of the each adjustment
items are set correctly referring below.
2-18: Confirmation of Fixed Value (step No.)
NO.
04
14
15
16
18
20
21
23
28
29 FUNCTION
H VCO
BRIGHT MAX
BRIGHT MIN
CONT CENT
CONT MIN
COLOR MAX
COLOR MIN
SHARPNESS
TEST MONO
TEST STEREO RF
04
170
90
40
30
65
01
35
00
00
2-15: SEPARATION 1, 2
Please do the method (1) or method (2) adjustment.
Method (1)
1.
2.
3.
4.
5.
Set the multi-sound signal generator for each different L-
ch and R-ch frequency (Ex. L-ch=2KHz, R-ch=400Hz) and
receive the RF.
Connect the oscilloscope to the pin 6 of CP601 and pin 7
of CP601.
Activate the adjustment mode display of Fig. 1-1 and
press the channel button (26) on the remote control to
select “SEP 1”.
Press the VOL. UP/DOWN button on the remote control to
adjust it until the audio output wave becomes a fine sine
wave.
Press the CH UP button once the set to “SEP 2” mode.
Then perform the above adjustment 4.
Method (2)
1.
2.
3.
4.
5.
6.
7.
8.
Set the multi-sound signal generator L-ch=1KHz, R-ch
=Non input and receive the RF.
Connect the oscilloscope to the pin 7 of CP601.
Activate the adjustment mode display of Fig. 1-1 and
press the channel button (26) on the remote control to
select “SEP 1”.
Press the VOL. UP/DOWN button on the remote control to
adjust it until the R-ch output becomes minimum.
Set the multi-sound signal generator L-ch=Non input,
R-ch=1KHz and receive the RF.
Connect the oscilloscope to the pin 6 of CP601.
Activate the adjustment mode display of Fig. 1-1 and
press the channel button (27) on the remote control to
select “SEP 2”.
Press the VOL. UP/DOWN button on the remote control to
adjust it until the L-ch output becomes minimum.
2-17: LEVEL
1.
2.
3.
4.
Receive the monoscope pattern (70~80dB).
Connect the AC voltmeter to pin 6 of CP601.
Activate the adjustment mode display of Fig. 1-1 and
press the channel button (25) on the remote control to
select “LEVEL”.
Press the VOL. UP/DOWN button on the remote control
until the AC voltmeter is 100
±
1mV.
2-16: FM LEVEL
1.
2.
3.
4.
Receive the monoscope pattern (70~80dB).
Connect the AC voltmeter to pin 14 of IC901.
Activate the adjustment mode display of Fig. 1-1 and
press the channel button (24) on the remote control to
select “FM LEVEL”.
Press the VOL. UP/DOWN button on the remote control
until the AC voltmeter is 75
±
5mV.
"A"
Fig. 2-2
White 100% Red 110%
Fig. 2-3