bentech 1 Posted October 30, 2014 Having 4 Speco Intensifier CAM connected to 12VDC . Since a few weeks , image is rolling or getting lines on the screen (video signal doesn't sync good). This is on all Speco Intensifier Bullet cams. Having a power dist box (12V) with other cams connected to it (dome) and they are OK. I change the power dist box just to make sure problem is not coming from it and samething. Question: Do you think by connecting them to 24VAC would improve the signal ? Share this post Link to post Share on other sites
ssnapier 0 Posted October 30, 2014 Is everything grounded / bonded properly? The only real advantage to 24VAC is when you have to cover a long distance. Share this post Link to post Share on other sites
the toss 0 Posted October 31, 2014 Is everything grounded / bonded properly? The only real advantage to 24VAC is when you have to cover a long distance. Power related earth loops are also reduced but I would ask bentech about his cabling. What is he using & how long are the runs? It sounds to me that it is not an earth problem but a vertical sync problem. Share this post Link to post Share on other sites
bentech 1 Posted October 31, 2014 Hi , Here are some infos: -I use a Altronix SAV9D as power distribution (12VDC) -I tried to increase the voltage to 12.5 volts , samething -Problematic cams are SPECO HTINTB8 -cable is RG59 with BNC compression connectors -There is a junction with an union -~800 feet long Was there for 2 years without any problem. Can it be termination (75 ohm) setting on DVR . Having a video tester ST893 , and signal seems to be OK on it. When connected to the DVR or LCD monitor , not good. See pic attached. You can see the lines at the bottom Share this post Link to post Share on other sites
bentech 1 Posted April 1, 2015 OK , fixed the problem by adding a ground loop isolator to the CAM that had lines. Stange , it was OK for more than a year without this. Thanks ! Share this post Link to post Share on other sites