Sharp mz-1d04 Service Manual page 7

Circuit to be checked
Video and its peripheral
circuits
Circuit to be checked
• Horizontal synchronization
circuit
Circuit to be checked
• Vertical synchronization
circuit
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PICTURE DOES NOT APPEAR
Observe the video signal at Q405 base on the
oscilloscope. Is the video signal on7
Observe the video signal at 0404 base on the
oscilloscope. Is the video signal on?
SYNCHRONIZATION NOT POSSIBLE
Horizontal synchronization
is not possible
1
0602,0603,
eG06, A623
and their per·
ipheral circuit.
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MZ-1 D04
NOTE: IF no picture should appear, try
to turn the sub-brightness knob
all the way to the right before
going into checking.
Check the
video input
circuit and its
peripherals
Input cable,
input socket,
computer
Horizontal and vertical
synchornization are not
possible
With the vertical synchro-
nization in normal condition
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VERTICAL SYNCHRONIZATION NOT POSSIBLE
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With the horizontal synchro·
nization in normal condition
·Check A510 (V-HOLD)
and its peripheral circuit.
VERTICAL SWEEP IS NOT DONE
7
NOTE: During the check, drop the
brightness to prevent the
CAT from being damaged.