its really simple projects
all you need is 7805 voltage regulator, 9v battery ,usb female and optional is diode and switch
total prize with diodes ,switch,battery,wires,.... is 1.5 or 2 dollars ( depends where you buy, how much,... i bought it in Serbia and here is 1.2 $ )
Step 1: Connecting
so first you will need is to insert 7805 regulator into the breadboard, make sure that every pin is in the other row.
in row of the first pin insert red wire. on 2nd row insert black wire, from that same row add one jumper(which will go to usb female).
3rd pin is output from 5v.
when you connect battery and regulator then add usb , now here is maybe one problem .
you have to connect positive to positive and gnd(black) to gnd pin.
the best way is to connect on one way and if that dont work than just switch wires
Step 2: Options
maybe one of most important things is switch
led is optional but its nice to have it just to know if its charging
this is simple instruction,really easy, for connecting all of this you need 10 minutes, i didnt solder because i dont have box yet and i want to try making something else
also , i will try connecting 6xAA alkailne batterys(thats also 9v ) but i am not sure about amperage
using single 9v is good but 9v volt battery wont last long ( 1 full recharge) so i will try out some other posibilitys. 6x aa batterys are good but i am not sure about their durability.