Atari 400

400 COLOR
BAR
TROUBLESHOOTING
(cont)
Verify
that each
o£
tfaa
foUowing levels
and/or
signal wave
forms
exist before procee<iing
to
the next step.
Use SALT
11, COLOR BARS.
locked
into the
continuous mode.
Is there 3.58MH2
oscillation
at R1S8
on
Motherboard.
Refer Figure
YES
Is there input
signal to
base of
Q107 Refer Figure
YES
Is
there
output
signal
from collector
on
Q107 Refer
Figure ,
YES
NO
Swap-out XlOl.
Q103
and
0104
NO
Trace
circuit back to
previous step
NO
Trace
circuit back
previous step
to
Is there
signal at
J107. Pin
1 Refer
Figure
NO
Trace
circuit back to
previous
step
YES
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