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What has caused distortion on this video?

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coshkun

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What can cause this distortion on the picture? We use video transciever.
**broken link removed**
 

Re: video distortion

This disturbance can be caused by line frequency signal interfering horizontal sync pulses or video signal. Check video signal, without clamping it, on monitor input. Check power supply for hum and it looks like you have half-wave rectification if this is a problem (faulty bridge rectifier).
Generally, horizontal synchronization is time shifted by interference.
Your picture is distorted in full width on the top and not only where marked.
My assumption is that you have checked for grounding problem.
 

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    coshkun

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Re: video distortion

We use battery on receiver.It heats too much.Maybe this is one of the causes of problem but i'm not sure.This situation sometimes occurs.
 

video distortion

Does the distortion vary with scene brightness?
Does the distortion disappear if you connect the camera directly to the monitor, without using the transceiver?
Have you tried another video monitor?

I've seen distortion like that when the horizontal sync pulses get messed up during the vertical blanking interval. Maybe your transceiver is doing something bad. Check the video signal with an oscilloscope or video waveform monitor.
 

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    coshkun

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Re: video distortion

Yes, distortion varies with scene brightness.
When we connect cam directly there is no problem.
We use an external tv card on laptop to get video.
We checked the signal with an 100 mhz tektronix digital scope.What do we suppose to see exactly.We see 5 microseconds sync pulses clearly but we don't see any difference between transmitting and receiving signals.
 

Re: video distortion

You should look at the frame timing (20ms) and not line and do not use clamping. Observe sync tips line and it must be straight. If not, observe tip variations due to the picture content (APL).
 

Re: video distortion

coshkun said:
What can cause this distortion on the picture? We use video transciever.
**broken link removed**
Click to expand...

add reconstrution filter to it
 

    C

    coshkun

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Re: video distortion

crossbow_123 said:
coshkun said:
What can cause this distortion on the picture? We use video transciever.
**broken link removed**
Click to expand...

add reconstrution filter to it
Click to expand...
What kind of filter can we use?
Thank you guys for your helpful replies.
 

Re: video distortion

can you give some links about video reconstruction filters?
 

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