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Old 04-14-2013, 06:00 PM
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wa2ise wa2ise is offline
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Join Date: Dec 2002
Location: USA
Posts: 3,147
Quote:
Originally Posted by lucvic View Post
I don't understand why there is a pulse superimposed probably coming from
horizontal transf to the video signal. automatic frequency control works properly so this pulse doesn't affect the image.
Sometimes the clip lead on the scope probe will pick up some of the horizontal flyback pulse, via magnetic coupling. And cause this waveform to get added in the scope to the real waveform you're trying to probe. Try repositioning this clip lead, also the path the scope probe lead wire could also pick up some horizontal, so try to route this away from the flyback transformer area.
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