Variable power supply
phil, Tue Sept 19 2006, 07:13PMWell i was originally going to mod an ATX power supply for a benchtop one. I need a power supply to run the PIC microcontrollers which require 5 volts. But after talking with some guys in the High voltage chatroom i decided to use the power supply for coilgun parts. So i went on a quest for a cheap variable power supply. I finally decided on the 0-12 volt one from Chaney electronics. It was small, and reliable. (
here are some pics of the build. you can get an idea of what the finished thing looks like so i dind't include a final pic. I had a problem with the fan though, it was a 12 volt fan and i tied the power leads to the binding posts for the output. only problem was that at around 5 volts it would start to draw power. and would make the output voltage oscilate from 5 to 4.3 volts. If that happened while working ona pic the Pic would brownout every time the voltage dropped below 5 volts. so i had to add a switch to turn off the fan while working on PIC microcontroller. I'm not too worried about overheating the power transistor at 5 volts, but it starts to get hot at around 8 volts. mockup of holes, left to right: switch, LED, last 2 are for potentometer
mockup of parts
makeshift vent
ghetto fabulous way of makeing a large hole :)
soldering the connections
Re: Variable power supply
Hazmatt_(The Underdog), Tue Sept 19 2006, 11:20PM
who said that power supplies aren't cool....because I think they are! I love these things.
Hazmatt_(The Underdog), Tue Sept 19 2006, 11:20PM
who said that power supplies aren't cool....because I think they are! I love these things.
Re: Variable power supply
phil, Wed Sept 20 2006, 12:43AM
Lol, let me restate that. MY power supply isn't cool. the real ones are. except those arou about 1000 dollars out of my price range.
phil, Wed Sept 20 2006, 12:43AM
Lol, let me restate that. MY power supply isn't cool. the real ones are. except those arou about 1000 dollars out of my price range.
Re: Variable power supply
Part Scavenger, Wed Sept 20 2006, 02:51AM
His wasn't that cool to start with either. Not to say it isn't absolutely flippin' sweet now.
Part Scavenger, Wed Sept 20 2006, 02:51AM
His wasn't that cool to start with either. Not to say it isn't absolutely flippin' sweet now.
Re: Variable power supply
Hazmatt_(The Underdog), Wed Sept 20 2006, 05:57PM
My psu started out as a bunch of transformers on a piece of fiber-board when I was 16. It has evolved a lot over the years, and even sports 4 continuous readouts!
It still has one last generation yet to come. An improvement which will let me pull a lot more current then I can now.
The present supply is pretty expensive and packed with electronics everywhere. The next one I will probably have to have a toroid made for it because I need a specific VA and lots of taps.
Hazmatt_(The Underdog), Wed Sept 20 2006, 05:57PM
My psu started out as a bunch of transformers on a piece of fiber-board when I was 16. It has evolved a lot over the years, and even sports 4 continuous readouts!
It still has one last generation yet to come. An improvement which will let me pull a lot more current then I can now.
The present supply is pretty expensive and packed with electronics everywhere. The next one I will probably have to have a toroid made for it because I need a specific VA and lots of taps.
Re: Variable power supply
phil, Fri Sept 22 2006, 03:37AM
I plan on getting a digital readout, or just a bargraph so i dont have to have a multimeter hooked up to see what the output voltage it.
phil, Fri Sept 22 2006, 03:37AM
I plan on getting a digital readout, or just a bargraph so i dont have to have a multimeter hooked up to see what the output voltage it.
Re: Variable power supply
Part Scavenger, Fri Sept 22 2006, 02:08PM
For a super cheap instant digital readout, you can get a voltmeter from Their yellow $10 one goes on sale for $3-4 quite often.
Part Scavenger, Fri Sept 22 2006, 02:08PM
For a super cheap instant digital readout, you can get a voltmeter from
Their yellow $10 one goes on sale for $3-4 quite often.Re: Variable power supply
phil, Sat Sept 23 2006, 01:27AM
Hmm, i guess i could do that. but i wanted to put those A/D converters i have to good use. I just gatta scavenge some 7 segment LED displays and i should be able to make one. I also need to change the fan thats on the power supply, it draws too much current, not to mention it has toner caked on it so whenever i touch it i get toner all over my hands.
phil, Sat Sept 23 2006, 01:27AM
Hmm, i guess i could do that. but i wanted to put those A/D converters i have to good use. I just gatta scavenge some 7 segment LED displays and i should be able to make one. I also need to change the fan thats on the power supply, it draws too much current, not to mention it has toner caked on it so whenever i touch it i get toner all over my hands.
Re: Variable power supply
Alex, Sat Sept 23 2006, 07:45PM
Sounds like a neat project, but I've got two things to point out:
1) The images on your page don't load.
2) From the Project Board rules: Be thorough. A link to a website isn't appropriate, neither is a short paragraph. When possible, include images and other media.
Alex, Sat Sept 23 2006, 07:45PM
Sounds like a neat project, but I've got two things to point out:
1) The images on your page don't load.
2) From the Project Board rules: Be thorough. A link to a website isn't appropriate, neither is a short paragraph. When possible, include images and other media.
Re: Variable power supply
phil, Sun Sept 24 2006, 03:58AM
Oh, sorry, i dind't read the rules
. I'll try to fix the pictures and i'll be more thorough next time. 
. but where would we have a conversation about the project?
phil, Sun Sept 24 2006, 03:58AM
Oh, sorry, i dind't read the rules
. I'll try to fix the pictures and i'll be more thorough next time. . but where would we have a conversation about the project?Print this page