My Vilar IP camera served me well for almost an year until I had to replace its power supply. The symptoms were strange - the camera crashed, the PTZ was not working, but yet it transmitted ok.
The new power supply didn't last that long and even the video transmission failed.
Therefore I digged out an old 230W computer power supply (PS) and started thinking on wiring it to the 5V input of my camera.
Cutting the original power cable to get a connector that will fit was easy. Next I had to find out that the (+) was the red wire, while the (-) was the black one.
In order to check the needed wires of the computer PS it had to be working. Plugging it in did not made the trick, so I remembered that ATX PS had a low-power switch. Googling this I came across a page that made the obvious proposal to short-cicuit pin 14 and 15 (PS on and GND).
Luckily I wear a switcher with self-made zip handle made of clip. I took out the clip, cut it in half and bend it to produce an always-on power supply :)
I measured the different currents and found out that the black out is again GND. I've been burned by even more obvious things so I like to double check things. The red one turned ot to be +12V, while the yellow wire was the needed +5.12V
I soldered the cable from my camera to the wires of the ATX PS (red-red and balck-black), checked that the (+) is +5V and (-) is GND and decided to gave the IP camera a go with the new supply.
Suddenly the camera movement was faster (it sloooowly turned left/right with the old supply) and it responded to all requests as if it was just bought :)
Now I intend to power my Arduino Nano circut with the same ATS PS.