Panasonic BT-M1950Y Service Manual page 36

Item Test equipment Test points
Adjustment
Adjustment procedure
locations
APC (PAL) Oscilloscope TP-48 C224( 4.43APC)
1. Connect a 1
o
Kn resistor between IC201 pin 13
Signal generator TP-49 R210(DL AMP)
and +B (12 V).
(Color bar, split C206(LISSAJOUS 2. Connect a shorting fixture between IC201 pin 14
color bar)
3)
and ground.
1
o
Kil resistor C207(LISSAJOUS 3. Connect a 5.6KQ resistor between IC201 pin 8
5.6Kil resistor
2) and ground.
Shorting fixture
C209 4. Adjust to synchronize the color bar with C224.
[Signal PWBJ 5. Remove the resistor and shorting fixture.
6. Connect an oscilloscope to TP-48 and TP-49
and display X-Y coordinates.
7. Adjust R21
o
and C206 to obtain the waveform
indicated in the figure. If inadequate, adjust
C207 and C209.
0
.....
*-
Adjust
(A)
(B)
8. Supply a PAL split color bar input and adjust
C224 to minimize coloration in the R-Y and B-Y
components.
Pulse cross Signal generator R570(V.SYNC) 1. Set the pulse cross switch to on.
(Color bar
[Signal PWBJ
2. Adjust R570 to eliminate luminance and burst
NTSC/PAL) signal variation in the V blanking period.
3. Supply a PAL color bar input.
4. Confirm absence of luminance and burst signal
variation in the V blanking period.
5. Again supply an NTSC color bar input and again
confirm absence of luminance and burst signal
variation in the V blanking period.
6. If variation is present, again adjust R570.
7. Set the pulse cross switch to off.
Chroma and Oscilloscope
TP-B
S02(CHROMA) 1. Supply an NTSC color bar to Video A.
phase Signal generator [CRT socket S03(PHASE)
2. Set the menu Filter Select to Notch.
(Video input, (Color bar) PWBJ [SERVICE MENU] 3. Connect oscilloscope to TP-B.
NTSC) 4. Alternately adjust S02 and S03 to obtain a
straight line waveform.
5. Set Filter Select to Comb.
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