Instructables

$2 Cassette Box Cellphone/USB Charger

Picture of $2 Cassette Box Cellphone/USB Charger


I love the Mintyboost power supply/charger Instructables, but wanted to look for something a little readily available that doesn't see much use anymore and that was a little easier to customize. Going through a few stores of odds and ends, I came across an old cassette tape collection, and there it was! I tossed in a $1.69 Radio Shack 7805 5 volt regulator (they have virtually every type of protection built in, including thermal overload, spiking, reverse polarity, etc.), and came up with this! It's easy, fast, and a great little charger that you can use with just about any DC power source to charge your cellphone, or, with a little extra effort, your USB! A big thanks to JDurban for his advice on this project!
 
Remove these adsRemove these ads by Signing Up

Step 1: The Regulator

Picture of The Regulator
You couldn't ask for an easier part. It requires no additional components to work, and you only have to solder to three pins. The DC power leads attach to pins 1 and 2 (2 is the common ground for both input and output), and pins 2 and 3 for the output... what could be simpler?
I got a voltage regulator but the guy didn't know what the hell he was selling so i had to guess. I'm fairly certain i got the right one but it still doesn't work. i also got 2 green 2.6v LED's if that helps. the one I'm using now is a yellow one. I dont know what it takes. i got it from and old PC. Can anyone either tell me whats wrong with it or give me any pics. That would be a great help. Thanks. Untitled.jpg
Untitled.jpg
Are you still there?
I kind of quit for a while but I still have the regulator and plenty of 9v batterys. I think I could make one now but have been busy lately with other things like trying to figure out if I should make a small ammonium nitrate & molasas bomb and set it off out in the country or go through the tedios task of turning it into sodium nitrate and then mixing it with sugar to make a smoke bomb. Also want to make something special for my girlfriend since valentines day is comming up. But after I'm done with thoughs things, I'll give it a shot again lol. ( I don't have a phone to test on anymore though so I'll try to borrow the mp3 that I gave my gf a while back.)  I'll let you guys know how it turns out. =)
You have a problem in your schematic!!!

The negative goes to the 2nd pin and out in the same pin(kinda need to have solder skill) 1st is positive in and 3rd is positive out!!!
kinda figured lol. it is over a year old, and i was just starting to learn back then. =)
Good for you!
P.S. You should make her a EL wire Heart.
nah cause were I live, it's kinda hard to get that stuff and I don't like to buy over net. (havn't done it yet lol) But you did give me an idea. I could try to make a heart pillow that can recharge anything that a USB will plug into. I could even make it into an instructable. =) And I know what your'e thinking, we already have alot. But IF I do, do this. Then I will be detailed and give a readable schematic, unlike when I first tried to learn. =)
how much voltage can the regulator tolerate?
5 to 37 volts i believe
35 volts (7805)
danukhan4 years ago
Never connect LED in series with voltage regulator.It will reduce input current to the LM7805 and LED may destroy.
will it give out put of only 5 v irrespective of the voltage applied?
i'm not sure but i guess. il ask one of my teachers when vacation is over
jehan601885 years ago
looks nice and simple! but I'm a bit confused (probably due to the mix of blurry pictures, and my lack of knowledge in electronics). If I wanted to be able to plug a usb device into it, I would simple go battery to regulator to usb? that sounds too easy!
what will be the current flowing?
please reply
Notn45 years ago
"good bye mr.furbie" xD
i would be Honored if you added this to my portable chargers group
babblin5 (author)  Yerboogieman6 years ago
I'd be happy to, but I can't find it... =)
georgejim646 years ago
are you sure the amps dont matter, because im thinking about making a usb wall charger.
Cool Instructable, I knew I saw the DC/DC picture before, great job, but won't this bust your item? Last time I tried something like this and it screwed up my iPod video's battery. :'( Nice evil Furby.
So long as you use the 5V regulator correctly, you shouldn't have a problem. Where people go wrong is using 6V or 9V without a regulator.
Nice! I had this exact idea recently. I botched the soldering job, but I'll get it working eventually (read: during the summer). I have to admit, my cassette cover was not as cool as yours.
Dude, Im so gonna make this 4 my ipod nano 2nd gen. Great little box. Maybe i should make 1 4 my buddy wu uses a purchesed used creative zen microphoto. We Always run otta battery! Thanks sooooo much!!!!!!!!!!!!!!!!
ventsi6 years ago
cool and cheap to make it here in Spain they sell simular for 36eur
cool, lol DC/DC. i like ac dc better :-P. not bad, any usb charger can be made with only a 5v regulator, usb cord, and power source :-). thats why i like these things cause there very easy to make!
Pro

Get More Out of Instructables

Already have an Account?

close

PDF Downloads
As a Pro member, you will gain access to download any Instructable in the PDF format. You also have the ability to customize your PDF download.

Upgrade to Pro today!