Instructables

Portable USB Power HELP!!!!!!!

I'm currently working on a project for my PSP, I work long hours away from power sources to recharge my PSP. So I'm trying to build a portable USB power device which I can recharge it with.

I've hacked the solar panels from two old garden lights, they had 2 AA rechargeable batteries in each and no over charge protection in the circuit.

I plan on mounting the solar panels on the outside of the PSP case and the batteries inside it.

I've mashed (really I have no idea of the theory behind electronics) this project up from the following people.....
http://www.instructables.com/id/E8XCQO72IQETVPJYZL/?ALLSTEPS
http://www.instructables.com/id/E1QBI60DAJEQZJHW8Y/?ALLSTEPS

My problem is I seem to be getting 6 volts instead of 5 volts coming out of the regulator, like I said I'm a noob in electronics and any suggestions would great.

http://static2.instructables.com/pub/FHE/TCUY/FHETCUYQBNEV2ZE6SC.medium.jpg

http://static2.instructables.com/pub/FEY/JNGP/FEYJNGP5GXEV2ZE6SX.medium.jpg

I hope this worked OK it's my first post.


photozz7 years ago
There is no way a 7805 should be putting out 6v unless it's blown. looking at the setup, with the 7805 as pictured, the left pin should be the input + from the 6v power source, the center should have a negative going back to the 6v source. The right pin should be the 5v output, and should also have a wire to the middle pin... Messing with the resistors will only cut your current down. not the most effective way to do it.
Ddaj7 years ago
I dont really have a clue but i do beleive that this is a simple way to cange the voltage from 6v to 5v. try using in series 2 resitor's 1 either side of the regulator (i have no knoledge on regulators so this may not help) one of them being 5X10 to the power what ever, the second being 1x10 to the same poewer. if i am right then this should spilt the voltage making their 5v on the regulator (i dont believe it matters which way around the resitors go)
Belleye (author) 7 years ago
1 down appeared to be a flat battery in the multi-meter. But now when I plug the charger into the PSP the orange light comes on to indicate it is charging, until I turn the unit on then it goes green, unlike when I charge it through the usb port on my laptop it stays orange. Tried an extra regulator but running them parallel made no difference. My theory was there wasn't enough amps getting through. Cheers for the links French having a read now.
Have you tried using larger resisters? Just an idea.
Belleye (author)  FrenchCrawler7 years ago
Cheers for the advice, what sort of resistor would you recommend? I'm like a total noob with electronics the components I have used so far I've copied from other projects.
Unfortunately, I too am much of a noob at electronics. So I'm unable to actually recommend the type of resistor, but from common knowledge of what most of the components do, I figured that it would be your best bet.

Here's some guides:
http://www.technick.net/public/code/cp_dpage.php?aiocp_dp=guide_res_cap_codes
http://xtronics.com/kits/rcode.htm
http://www.lalena.com/audio/electronics/color/
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