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NO VERTICAL
SWEEP
+12V is observed at pin 12 of (C401.
YES
Substitute [C401 for test purposes.
NC COLOUR
Readjust tuning and colour controls.
NG
NO
Check D460 open
or short R463, R466
open C463, C467
short
Substitute 1C201 for test purposes.
NG
Check the waveform at pin 10 of 1C401.
LW
3.8Vp0
Check the voltage at terminal ''20"'.
It should vary from OV to +12V
with colour control.
Check VR902, R401
open C401 short
Service Tip
Inject AC signal through the TEST PROBE
{shown in Figure A} to Q442 base.
Vertical sweep is widened,
Check the colour
control (VR294)
Remote control
Check the voltage at Pin 4 of 1C201
+110V is observed at Q440 collector.
Check R443,
R447
R448, VR440 open
NO
C443, C444 short
Check C440
short
+110 is observed at Q442 collector.
Check 0441, 0442,
C448 short R441,
R424 open
Almost Zero
Approx. +9V
Check the voltage at Pin 5 of [C201
Check C202
short
Check Q441, 0442, R445,
C445 open C441, C442
short Deflection Yoke
Almost Zero
Approx,
+9V
pecs
Check C204
short
NO
Check C205, C207
Check the waveform at Pin 7 of 1C201
short R205
AAA
0.25Vp-p
Disconnect Service Tip, and check the three
coloured lines on screen. Then readjust grey scale
tracking (by red, green, and biue bias controls)
Check the waveform at Pin 6 of [C201.
POOR
GREY
SCALE
|
m
nr
YES
NO
1,.0Vp-p
Check the waveform at Pin 8 of 1C201
|
| | |
Check X201 open
or short, C206
C207 open
Loss of red tine
Loss of blue line
Loss of green line
YES
Check the waveform at Pin 18 of 1C201.
|
12Vp-p
Check Q430, R434
open 0430 short
NO
Check Q611, VR611
R613, R611, R615
L239 open
Check 0601, VR601
R603, R601, R605
L238 open
Check Q621, VR621
R621, R623, R625
1240 open
YES
Check R236 open.
Check the voltage at Pin 26 of 1C201.
Almost Zero
Approx. +10V
Check C240 short
Check the waveform at Pin 29 of C201.
0.8Vp-p
NO
Red line predominant
Green line predominant
Blue line predominant
Check Q611 short
Check Q601 short
Check 0621 short
YES
VR611,
R612, R239
C615
short
Check the voltage at Pin 24 of IC201.
VR621, R622, R240
VR6O!1, R6O2, R238
C625 short
Check C246 short,
C245, C247 open.
+9V or more
Approx, +7V
Check C238 short
Check C201 short
L230, VR240 open
R201 open C240,
C244 open
No Horiz. & Vert. Sync
No Vert. Sync
No Horiz. Sync
Check 1C401, C405
Check 1C401, V491,
VR410, R407, R409,
CA10, C411 open.
Check 1C401, VR492,
short C404, R405,
R402, R403, R404
R406 open
open C402 open or
short
TEST PROBE
NARROW
HORIZONTAL
WIDTH
Check +110V supply (B1) at terminal "1T".
To terminal ''3E
poses
ee
+100V or tess
Approx. +110V
a
10K
$3
Trouble ts in power supply circuit.
Check T460
To terminal
''3F"'
i
To ground
0301 short, C308, C312, C321
Shielded pad
R305 open and T301 short
Figure A
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