Video Signal Issue

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superslack
Posts: 78
Joined: 08 Feb 2016, 23:58
Location: Virginia

Video Signal Issue

Post by superslack » 13 Jan 2018, 22:46

Hey guys,

I'm tidying up my night vision goggles. It is simply an Eachine EV800 FPV goggle set and Foxeer Night Wolf Camera. I wanted to run the camera off power from the goggles and run the video signal in as well.

I hooked up leads to the 3.7V battery power and then used an LM2577 based converter to boost the voltage up to 12V. I soldered the video lead to the pin where I have putting the external AV cable.

It works fine, except I have a bunch of screen noise now. I can still hook up the camera to run with separate power and put video in the external AV in port. That reduces the noise back to almost nothing.

Any hints on how I could reduce the noise with the internal wiring?

Image20180113_143856 by Undrcoverrednek, on Flickr


Camera hooked up as shown in the pic above. I removed the connector and soldered the wires together. No change in noise.
Image20180113_145733 by Undrcoverrednek, on Flickr


Camera hooked up with external power and video going into AV port on goggles.
Image20180113_145637 by Undrcoverrednek, on Flickr

hutty33
Posts: 54
Joined: 05 Oct 2013, 19:29
Location: Houghton Regis, Bedfordshire

Re: Video Signal Issue

Post by hutty33 » 14 Jan 2018, 00:23

I won't try to explain a fix as I'm not that clued up with it and I'll likely get something wrong, but do a google search for 'fpv camera noise' or similar searches - there are 2 or 3 cheap and easy ways that may sort it.

phoenix
BRUCE ALMIGHTY
Posts: 4836
Joined: 09 May 2012, 14:40
Location: Aberdeen

Re: Video Signal Issue

Post by phoenix » 14 Jan 2018, 08:46

It's coming from the boost converter - they're infamous for generating electrical noise which appears on video signals.
You might improve the situation with some 0.1 and 1 microfarad capacitors across the 12v output of the converter, but there's no guarantee that would work.
The best solution is to run the camera from a completely separate battery.

Cheers

Bruce
LAND ROVER - THE WORLD'S WORST 4X4 BY FAR

superslack
Posts: 78
Joined: 08 Feb 2016, 23:58
Location: Virginia

Re: Video Signal Issue

Post by superslack » 14 Jan 2018, 13:49

Thanks for the help, gentlemen. I will try something a little different based on your input.

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