tomdlgns 0 Posted December 14, 2014 i am experiencing an issue with a 3 year old goevision system. custom built pc, legit geovision card (purchased from an authorized retailer where i buy all my cards), using a 30 inch tv as a monitor (vga port) and not the composite video out from the geovision card. everything has been working fine for about 3 years. the system is set to launch on start up, record, and go into full screen mode. a few days ago something odd happened. not sure if they are related or if maybe two things are happening... - all cameras show video lost (tested power supply, working, putting out 12 volts. if power is cycled (turning off the power supply) the cameras come back for about 15 seconds then it switches back to video lost. (exiting in and out of full screen mode doesn't do anything...continue to show video lost) - all cameras switch to black overlay on the cameras (no video lost is displayed) and you can see the camera names. DSP option is enabled (has a check next to it). if i exit full screen mode, i see the video feed come back. if i enter full screen mode, everything goes back to black. if i disable DSP, nothing happens. if i enabled it, nothing happens. the only thing that fixes it is to close geovision and open it back up. something to note: - 1 camera is bad. video flickers in and out and the picture is barley noticeable. i am not sure if the video signal from this feed is causing any issues with the two things i explained above. i am not on site and i can't unhook the connector, but i can login and disable it if i see the issue occur again. i want to leave it as is for testing/troubleshooting purposes, for now. thanks. Share this post Link to post Share on other sites
jeromephone 6 Posted December 21, 2014 If you have a bad camera or bad power supply it could cause this we had a system that did something similar and it was a power supply problem. We found that if possible use an isolated power supply so if on camera or lead was bad it would not affect the others. The isolated ones are more money but I think they are worth it . Share this post Link to post Share on other sites
gb5102 0 Posted December 21, 2014 If you have a bad camera or bad power supply it could cause this we had a system that did something similar and it was a power supply problem. We found that if possible use an isolated power supply so if on camera or lead was bad it would not affect the others. The isolated ones are more money but I think they are worth it . ^I agree. Use isolated power supply(or individual wall-warts...yuck) if using 12vdc cams, or better yet use dual-voltage 12vdc/24vac cams. Dual-volt cams have their power section isolated from video section internally, which also makes them much more resistant to ground loop issues. To be absolutely sure, you will need to go onsite and connect 1 camera at a time and see if the problem appears only when the 'bad' cam is connected, but I would bet that is your issue. Share this post Link to post Share on other sites
tomdlgns 0 Posted December 21, 2014 you guys recommend i switch from a centralized power source to individual power sources for each camera? that will require 16 outlets. i could see this for testing, but not for a permanent solution. thankfully this issue hasn't occurred since last week, if it has, the owner has not mentioned it. being that this is his only view of the cameras, i have a feeling he would tell me the minute it occurs, again. i do plan on going back to swap out the bad camera, but if this occurs again, i will log in and disable the bad camera. Share this post Link to post Share on other sites
gb5102 0 Posted December 21, 2014 you guys recommend i switch from a centralized power source to individual power sources for each camera? that will require 16 outlets. i could see this for testing, but not for a permanent solution. It sounds like the main complaint here is related to a defective single cam. You didn't mention anything about rolling bars or other 'normal' ground loop related artifacts, but since all cams are being affected by this, it makes me think ground loop. Most(all?) 12vdc cams internally connect the power ground and video ground(ground loop). I am curious if disabling the cams in the software would have any effect, I don't think it will if my theory is correct and this is an electrical issue. I have definitely inherited a couple of bad installs with horrible ground loop issues where the only way to fix was to isolate the power. This can be done by using individual wall-warts; or by replacing the central 12vdc supply with 24vac supply and either using 24vac-12vdc converters at the cams OR replace cams with dual voltage models. Obviously the individual wall-wart option is cheapest but yes you will have a few outlet strips full of power supplies...and much better picture quality/no more ground loop issues... Keep us posted, I'm interested to hear what you determine. Share this post Link to post Share on other sites
jeromephone 6 Posted December 22, 2014 Look up altronix they make a 24 volt isolated power supply which is like individual wall warts but is in one box with multiple outlets. Share this post Link to post Share on other sites
