jrc

I recently installed 4 outdoor 1080p HD cameras at my house. The cameras switch to IR mode at night and have IR LEDs to provide illumination. I have a problem with stationary horizontal bars in the video from one camera that only occur at night. To check whether the problem is with the camera, I switched this camera out for one of the others that had been working fine. The problem at night continued. I tried re-routing the cable in case there was some interference on the line and the problem continued. After some online research I see that the problem of horizontal bars can be caused by a ground loop, however I don't see how that could be possible in my installation. There is one power transformer for the cameras that is plugged into the same outlet as the DVR. This transformer has 4 outlets, one for each camera. The cables that run to the cameras are siamese, with the RG59 cable for the signal bound to the power cable. In this case, how could the ground level voltage at one of the cameras be different from the ground at the DVR? Does this sound like a ground loop problem or something else? Why would it appear only at night? Any suggestions? Here is a photo of the problem: https://www.dropbox.com/s/6haw81czt8y626g/cameraProblem.jpg?m Thanks for any advice.

Cameras are Lorex LBCHD2050. What kind of cable would provide the best video signal? I still find it strange that the image is fine during the day. The problem ONLY happens at night in IR mode. Here is a link to the camera on the Manufacturer's site: http://www.lorextechnology.com/Security-cameras/HD-security-camera-with-140FT-night-vision/prod290012.p?_DARGS=/site/search/include/searchResultItem.jsp_AF&_dynSessConf=3736594858532229895&/lorex/ui/UserContext.contextLocation=products&_D%3A/lorex/ui/UserContext.contextLocation=+ Cable is 100' of this: http://www.lorextechnology.com/security-camera-cable/200-FT-RG59-high-grade-Siamese-video-power-coaxial-cable/prod330006.p?_DARGS=/site/search/include/searchResultItem.jsp_AF&_dynSessConf=3736594858532229895&/lorex/ui/UserContext.contextLocation=store&_D%3A/lorex/ui/UserContext.contextLocation=+

Thanks, I am waiting for my ground loop isolator to arrive, as I decided it would be worth a try. Per the suggestion of the eariler poster, I did try switching the power and that did not make a difference.

>Have you tried switching around the power connectors on that multi power adapter to see if it's one specific power barrel that's shot? Yes, I think I did do that, but I'll switch the power connections around again tonight just to be sure. >Tried a new 4-way power supply? Tried a single power adapter just for that line? No, I only have tried the one power supply. I might have some others lying around that would work, I'll have to check. >Why didn't you use cat5 with POE for the cameras? 100' RG59/power cables came with the cameras, so that's what I used. For the record, the camera is mounted to a wood soffit under the eaves. The camera itself is not in contact with any metal on the house. Thanks for your thoughts.