home-made power supply - diyAudio
Go Back   Home > Forums > Design & Build > Equipment & Tools
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Equipment & Tools From test equipment to hand tools

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 26th September 2011, 02:34 AM   #1
diyAudio Member
Join Date: Apr 2011
Location: Anchorage AK
Default home-made power supply

so, i went ahead and tackled the little project of building my own power supply for my bench testing. first, i started with a vintage powermite charger to house it. of course, being old, and the abuse i put it through years ago left the transformer a tad cooked, lol. anyways, for the 2nd donor, i had an auto-sensing "10a" charger that one day stoped sensing the battery connection, so i opened it up and found that it housed a 25a+ transformer in like new condition. the setup was 2-part secondary (12+12) each, with a single diode. i didn't really like this, so when i set it up, i went with a pair of full bridge rectifiers and ran in series. after hooking it up, i found a faulty switch in the powermite, so bypassed that to take readings, then a bad 25a cb that came with the transformer (probably why it stopped sensing, in hind-site, lol), abd aside form that, it wanted to go 28v, which i thought might happen. so, my thought, is to run the primary side from a standard 125v lightswitch dimmer. just trying to get some thoughts on how this will work, or problems. all i can see from the dimmer is a pot/switch, and a transistor "1400"or "14000" the last 2 "0" s overlap. my first thought is that this is just s quick fix, and the nature of how i'm cutting it down is going to lead to too much voltage drop as current demand increases. also, i don't want to run the voltage too high when current demand drops. now, i do plan on running the outputs through a choke and 1farad capacitor to smooth things out, but i don't want the cap to build too high of voltage..... perhaps, i'll just go get a spare 24/12v step from work, but that would take me a month to get, and i would like to use it before then....... i know the correct answer i would tell someone is to just get6 the proper transformer, or deal with the linear rectifier setup, but i just want to make this work as a challenge.......
  Reply With Quote
Old 26th September 2011, 05:12 AM   #2
diyAudio Member
Join Date: Apr 2011
Location: Anchorage AK
pooo, it did just what i thought. ran dropped to half dc voltage under load on a halogen, and popped it at15v, then jumped to 28 unloaded.... i can't have the voltage creeping that high... on to the next plan...
  Reply With Quote
Old 27th September 2011, 11:33 PM   #3
diyAudio Member
Join Date: Apr 2011
Location: Anchorage AK
ok, i was being a dummy. it was a phasing issue having the common in the middle of the secondary windings, so i split it into to separate windings and cot the desired voltage. however, the rectified voltage now seems to be running with 5vac on top of that. i plan on smoothing it out with the choke i built on a transformer core, but i'm worried about just how much current it runs with the ac being absorbed by the cap. i used a 15000uf 50wv cap to take readings, and it held fine, and the dc sag dropped, also, it allowed the current to nearly doubble back to where i wanted it to be. the setup is going to be using the 1farad cap i had laying around, but i'm just not 100% sure on the safety of it
  Reply With Quote


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
50 Hz in home made power amp zoubour Solid State 13 7th January 2011 07:06 AM
Made in China,low cost,high quality,electronic components,power supply etc hang Vendor's Bazaar 1 16th September 2009 12:44 PM
Home Made Tubes?? has anyone made one, is it possible?? John Biles Tubes / Valves 7 11th December 2005 01:29 AM
Home power supply for car amp? Ignite Solid State 9 14th June 2002 11:04 PM

New To Site? Need Help?

All times are GMT. The time now is 01:13 PM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2