I am a member of an urban search and rescue team and, as such, am required to have a communications device other than a radio. Obviously, during any search and rescue mission, I would, generally, not have ready access to an electrical outlet (primarily, because there would probably be no power), so, I purchased a back-up power pack using 2-1.5V AA's, which may not be enough, since the power requirements are 5V. The previous cell phone that I had was easily "wired" to connect to a battery power pack; however, it "gave up the ghost", so, I was issued another one that has a mini-USB port for the charger. I purchased a 3-foot cable with mini's on both ends and cut it in half. (The reason for the long power cord is that the power pack was not secure to the cell phone and could easily and, unknowingly, fall off, so the additional length allows for the power pack to be placed in my pocket and the phone in a holster.
Four wires, Red, Black, Green, and White were found. Opposite end will have a mini-pin plug, with a "hot" connection and a "ground" connection.
To the question: Is the Red connected to the "hot" side and the Black connected to the ground? It's a new phone, issued to me by my employer and I don't care to ruin it. Thanks to all who may respond. I look forward to receiving the information. Jack.
Check this page out:
Basically, exactly what you said, red is 'hot' (positive) and black is ground (negative).