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TROUBLESHOOTING CHARTS
NO
Approx. +40V
Zero
+10V ~ +20V
Check 0308
Is 2A FUSE (F1001) blown out?
open
YES
NO
ts B0OmA FUSE (F301) blown out?
Check D301 short C305,
C308, C1001, C301
short
Check 0306
open, C312
short, T301
open
NO
Check the voltage
/ ~=—s both ends of C308.
+300V or more
Check the waveform
at 0304 collector.
520Ve-p
OK
Check C315
short
Check 0301, 0302, 0303
open, 0305, D307, open
0307, 0320 short, C314
open or short, C320,
C323 short, T301 short
Zero
Check, 11001, L302
R301, AC cord
$SW1001 open
NO
YES
{DC only)
Check the voltage between
collector (+) and emitter (—)
of Q304.
Check 0303 short
0306 short, 0320 open
C321, C460, C461 short
and 7301 open
+300V or more
Zero
Check R318, R313
open and T301 open
Check 0304 open R302
R314, C313 open
and T301 open or short
INTO MA)
0} 1
OME\LOm1O10]\ 10)
All bands
YES
NO
+12V is observed at
pin 4 of 1€101.
NO
VH
Check
C125 short
VE
Check
C122 short
Check D101, C112
C113 short R125,
YES
+4.5V is observed at
pin 2 of 1C101.
L107 open
-
—
tl
ty,
Check C114,
Check the waveform
C115 short
at pin 29 of IC 101.
2.5Vp-p HORIZ,
YES
NO
+5V is observed at
Check !C101
Q201 collector.
C116 short
NO
Check Q201, C247 short
R213 apen
.
YES
Check Q201, R132 open
X132 short
DARK
OR
NO
RASTER
SOUND
OK)
Picture tube heater is lighted.
YES
NO
Check the picture tube heater continuty
Disconnect the Service Tip.
A horizontal tine will appear.
AC 6.3V supply circuit and picture tube socket.
_ C630 short L631 open
YES
NO
+12V is observed at pin 22 of 1C201
NO
Reconnect the Service Tip.
Set contrast and brightness controls
to maximum.
yes
Substitute 1C201 for test purposes.
Check 0230, C249, C233,
C234 short L201, R190
open
Check the picture-tube screen
circuit (SCREEN VR, R465,
R631, C466, C631) and high
voltage at picture tube 2nd
anode read.
Check 0430, 0211, 0213
C217 short R435 open
C431 short or open
Check the voltage
both ends of C312.
Approx. +3V
Check +110V supply (81) at terminal "17".
Check 0302
0305, D309
short C310
R306, R308
T301
Picture Tube Heater is lighted.
Check C151, R124
open C152 short
NO RASTER
NO SOUND
YES
Check C463 short
R463 open
+110V of more
Trouble is in the Horizontal Oscillator,
Drive, or Output Circuits,
Check the following paragraphs.
OB8VeED
Check the waveform at 0450 base.
cel
Agel
YES
Check the waveform at 0451 base.
YES
NO
Check 0451 open
Check the waveform
R460, T460 open
at 0450 collector.
NO
Check 0451
short, L450
T450 open
NO
Substitute {C401 for
test purposes.
NG
+12V is observed at
Pin 15 of (C401.
YES
Check the waveform
at Pin 2 of 1C401.
Check 0450
short and R450
YES
4.2V0-0
Check 0450 open
R452, C451, C455
short, and T450
open
Check VR491, VR410
R408 open and C412
open or short
NO SOUND
Inject AC signal through the TEST
PROBE (shown in Figure A) to
pin 10 of 1C161.
A hum is created.
NO
+18V is observed
at pin 3 of IC161.
YES
+12V is observed
at pin 13 of 1C101.
NO
Check D320 open
or short L320, T301
open C322 short
YES
Substitute 1C161 for
test purposes.
YES
tnject AC signal through the TEST
PROBE to test point TP-P.
A hum is created.
Check C158, R158
open C175 short
Check C161, C162, C163,
C165, C167, C168 short
C166 open and speaker
Check X151, C153
short T7151, C154,
R153, R157 open
Check X151, C155, C156,
C157, C163, R160, R162
open
WEAK
VIDEO
Substitute 1C101 for test purposes.
NG
Check the Tuner AGC voitage at terminal 1P''.
Almost Zero
+4V, +7V or more
Check VR101, R121 open
C123, C124 short
Check X101 open or short
C102, R102 open
C105, C106 short
Or
180Vp-p
gts
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