I have two 12v batteries that I'm regulating down to 7.4v and 3.3v. The diagrams I drew up show the setup for one of the 12v batteries, so it will all be repeated on the other-side too. you can see in Diagram 2 where the other battery meets up with the regulator PCB.
The switch I'll be using will connect ~left and middle~ - ~middle and middle~ - ~right and middle~ .. so when the switch is centered no power goes anywhere, when the switch is to the left it awaits you putting the cable into the charge jack, and when the switch is to the right it sends the power to the regulator PCB.
Both the Left and Right pins on the switch are hooked up to the positive on the battery, and the negative is connected to the middle pin.
Here's the diagrams, let me know what you think about it, and if it'll do what I'm hoping it will.
If it works, everyone's free to use it! give some thanks so I know I'm appreciated
Oh, one other thing I'm hoping this setup will achieve.. is if your batteries start getting low, you can just switch one side over to the charging plug and charge that side, while the system just runs off the other battery!
Click on the thumbnails to view bigger size:
