9 volt USB hack

Inspired by losing power in the field and in need of a phone call, with a little research, I found a hack that'll suit my need!  A 9 volt battery, 7805 regulator, and a USB reciever encased by sugru... I love modern technology! 

wow !!!! this looks awesome, what components did you use to make this ? I want to make one...

Awesome hack it'd be cool if you put it on Instructables too!

I actually have a buddy that wants one, so I will make an "Instructable" when I make his.  This thing is a huge hit with my Marine Corps buddies!  I really want to make his adaptable for iPhone use... a few resistors and I will have it!

awesome, I also need one for my iPhone, can't wait to see your solution. I will be using a rechargable 9V for mine.

Very excited.

James, I just ordered everything I need for the iPhone capable version, so it is on it's way!  Thanks for your comments and anticipation!  I will definitely build an Instructable for this one, SUGRU and all!  I have many folks waiting for this, mainly, Marines(for an upcoming field op)!!!

Please note- this is not an everyday use charger, but more or less, last ditch effort to get one or two EMERGENCY calls or Facebook updates, while away from modern conveniences... I will include that disclaimer in the build, and why!  Thanks buddy!

Nice idea for all those poor iPhone users whose batteries are welded into the phone..! :D I had a similar idea but using a switching regulator (boost convertor) instead of the 7805. Regulators like the 7805 are very inefficient maybe 60% at best as in this case they have to waste 4V of energy in dropping from 9V to the desired 5V, whereas switching regulators can be at least 90% efficient... :) Swapping the 9V alkaline for a rechargable as James suggested will increase usage time but still a lot of wasted energy. A better bet would be to use any '3.7' volt LIPO mobile phone battery, feed that into a boost convertor like this one from Sparkfun:

https://www.sparkfun.com/products/10255

... this will provide at least 500ma which is up to the standard current supply for any single USB 2.0 port ( so in theory should be able to power any single USB device ) and then feed the resulting 5V output to a female USB connector and wrap the whole lot up in sugru... :) Usage time will be dependent on the mAh of the LIPO but you can get upwards of 2000mAh about 4 times that from a rechargable PP3 ( 9V ).

Beware of some 9V rechargables though, they may be advertised as 9V but in reality only output around 7.2V which is just about verging on the lower limit for use with a regulator like te 7805 which needs around 2V of 'head' to operate properly... ;)

As much as I appreciate your vast knowledge of mAh and LIPOs and the like, I must re-iterrate this is NOT an everyday charger, yet, an emergency use ONLY.  This hack is for those that are not dependant upon their mobile devices, therefore, the desire for a rechargable unit would be not require.  If that were the case, one (myself) would have posted a model more suitible for such use.  I was simple showing off the versitility of sugru and how I aplied it to my hack.  Please feel welcomed to share YOUR genius , and post at your will.  I can accept your many ideas, if I did not know of this before hand.  The practicality of the use of sugru would be obslete, and this thread would be useless to everyone.  James, still working on an iPhone friendly EMERGENCY CHARGER for you!!! Semper Fidelis!

Don't get me wrong, I think your idea is a great one! I was only trying to offer what I thought were a few helpful hints, in particular if you were thinking of making a second version. I certainly didn't mean to cause offence, my apologies...