Hi guys this is my first time so be gentle. I'm trying to create a portable power source out of rechargeable battery's for all those PSP's, ipod's and such. But what I can't figure out is where on the circuit to put female power port to charge the rechargeable batteries? To give you guys an idea of what I'm working with the circuit contains the following > switch, led, 2 rechargeable 9 volt batterys, USB output port and of corse 1 female power port to charge the batterys. Any help is greatly appreciated.