Hello all,

I have been browsing these forums over the last few days and there is tons of great information here. I noticed a couple ppl with similar problems here and I have followed the steps which were recommended to them but it seems like I am having no luck figuring out my problem...any help would be greatly appreciated!

I have a 2 camera set-up at home with a 4ch stand alone DVR. The camera's are vandal proof domes, 1/3" sony ccd colour with IR. The problem I am getting is only in one of the cameras. The picture flickers with this slightly whitish interferance that triggers the motion setting to record all the time. Not really bands or any rolling type interferance but rather slightly flickering picture. It is more apparent at night. I am using seperate 12Vdc 1160ma power supplys for each camera which i have tried swapping around to no avail. At first I thought it was my wiring, which then i re-crimped both BNC ends and tried moving my wiring and adding ferrites everwhere but to no avail again. I also tried grounding my DVR, camera and power supply's which did not seem to do anything either. After slapping myself in the head, i checked the camera directly with a test monitor (disconnecting the main RG6 run but keeping the power run) and the problem was still there. So i ruled out the video line being the problem. All this time I was thinking "ground loop, ground loop"...but it cannot be the case anymore with the main video line dissconnected right? I also know that it cannot be the power supply as the other camera is fine and swapping power supplies yeilds the same results. I tried shutting off the circuit breaker in the garage (the problem camera is mounted outside the garage) to see if there was any possible interferance from anywhere in there causing the problem but to no avail. Also tried moving the power supplies from in the garage to the basement. Both camera runs are about 50ft each.

Now here's the weird part.
When I dissconnect the power or unplug the power supply for a minute then reconnect, the problem dissappears but only to come back again within 1-2minutes! Does this mean that something inside the camera is resetting or taking awhile to "kick in" again the give the flickering problem? like maybe a bad capacitor or AGC??
The last thing I can think of to resolve this problem is to possibly try a ground loop isolator. Do you guys think this makes sense to try or am I having a camera problem?

Sorry that was a little long.... please help...

Last time I had this kind of problem (where disconnecting/reconnecting was a temporary fix) it turned out that the coax had been chewed by mice. The wire still had connectivity, but created an effect where the wire acted as a capacitor - once it got 'charged up' the camera signal dropped out.

Can you recheck the entire length of the wire for damage?


The other things I did to troubleshoot included swapping two channels on the DVR to see if the problem stayed with the DVR channel input or stayed with the camera. I also used a different power supply and even a different camera.

thanks for the reply Scruit,

Yep, I double checked the length of the RG6 and all is ok. Also, switching inputs on the DVR makes no difference, the problem follows the camera.

I think it's looking to be a camera problem...

Try swapping the cameras around to see if it stays with the camera or stays with the position, what are the camera's mounted to?

The Camera's are mounted to the aluminum soffit of my house. I have tried grounding the bnc connector to the soffit via ground wires and screws but that didn't help either. I will try swapping the camera's around on the weekend if it gets better weatherwise.

One thing i have noticed though....as the weather gets warmer...the problem seems to be less. like I mean, at -13C the flickering is really noticable......and tonight at -3C, the flickering is not that bad at all??

Is your RG6 CCTV rated (copper) or cable tv (alum) type?

Are you using premade cables? Do you have a BNC to RCA adapter at each camera?

Replace the adapter, and that should clear up the problem.

Otherwise you need to take a small TV out to the camera, and set it on the ladder. This TV needs the yellow video input (composite). Plug the video from the camera in to the TV. Do you have the interference now? Then it is a camera problem.

If the video is clear, then you have a cable ( or a connector) problem.

What do you think?