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No spot on CRT screen
No spot on C RT screen
(All CRT voltages
correct)
Retrace blanking in
operative
No focusing
No horizontal positioning
No vertical positioning
Astigmatism control in
operative
No sweep (hor. ampl.
0. K.
checks
)
C RT CIRCUIT
High voltage rectifier tube, V3,
defective
Filament leads broken
No voltage on second anode
Note: Spot may be deflected off
screen. Adjust V-POS . control for
equal voltages from CRT pins 6 & 7
to ground ( V. defl. plates) and H.
POS . control for equal voltages
from C RT pins 9 & 10 to ground
(H. defl. plates). The spot should
then be centered. If either adjust
ment is impossible, refer to the
vertical or horizontal amplifier
sections.
Defective CRT (V7)
C 12 open
Broken lead from the sweep fre
quency generator to the cathode
of V7
R21 defective
R19 defective
Note: R2 1 is the focusing poten
tiometer. Its action is dependent
on the setting of the astigmatism,
potentiometer R19. For best
focus , both pots must be adjusted
simultaneously as an initial ad
justment.
Refer to horizontal amplifier
Refer to vertical amplifier
R19 defective
SWEEP CIRCUIT
Sweep Selector switch is not set
to sweep positions
Lead or leads broken
V4 defective
S3 defective
R36 defective
33
Replace
Repair
Check circuit. Repair if necessary
Replace (V7)
Replace
Check if necessary
Replace
Replace
Replace
Set Sweep Selector to any of the
sweep positions
if
Check and repair
necessary
Replace
Check. Replace if necessary
Check. Replace if necessary
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