Top critical review
42 people found this helpful
Power switch design is flawed
on October 16, 2011
I read the other review about power being provided even when the switch was off and assumed that person had gotten a bum unit. So when mine arrived I tested it with my meter before plugging the cameras into it. Everything worked as expected so I went forward with the install. As soon as I attached the negative lead from my camera to this power supply, all the green LEDs lit up and the camera started working. The problem was, I still had the power switch OFF! That bugged me and since it's such a simple circuit and I had to open it up and see if I could fix it. Once I took it apart and saw how it worked I immediately saw the flaw in the design. The positive terminal is always hooked up to the leads and the power switch opens or closes on the ground supply. This works fine except that this is a camera power supply and every camera I have has a shared ground between the power lead and the BNC connector. So the moment you hook up the ground wire of the camera and you plug in the BNC connector to your DVR/TV... you just grounded the camera and then the circuit is completed regardless of the which postion the power switch is in. They should have switched the +12V lead to prevent this ground problem.
If you have any electronics skills, it's pretty simple to fix this circuit. I fixed mine by altering the design to switch the +12V lead. This requires just a little soldering, breaking a trace on the board and adding a jumper wire. Now it works like it should. I should have never had to do this... I felt like I should have returned the product and just built my own supply from Radio Shack parts but it likely would have cost more so that's why I chose to fix this. If you can live with the power supply always on then it seems fine, but I like my power buttons to work. Find something else.