i think the wire is the power supply, the send to the recording device, and everything else you may need to send to the camera and back to the recorder...i saw on another site that you need a panasonic 9000 vcr to recieve from this camera...my problem is i got three batteries and an ac supply for my camera and have no possible place to use them onthe csamera,,,thats why i assume the power must come from tyhe wire in the back and god only knows where these batterires are used...