Go Back   Home > Forums > Amplifiers > Power Supplies
Home Forums Rules Articles Store Gallery Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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
Reply
 
Thread Tools Search this Thread
Old 18th March 2007, 08:30 PM   #1
Nordic is offline Nordic  South Africa
diyAudio Member
 
Nordic's Avatar
 
Join Date: Sep 2005
Default 2 secondaries ,2 rectifiers and 2 regs, - rectifier overheats

My transformer has 2 12V secondaries.
Marked as pin 1 + pin 3 and pin 2 + pin 4.

Now the idea was to use each secondary to power 1 channel of a headphone amp... each with its own rectifier ... wich I made with big diodes (all I had in the box) in turn connected to a Voltage reg after some CCC filtering, I have not connected anything further than the regs, one measures 12.1V one reads 11.9V (100v range so not too accurate)....

What bothers me is that the diodes became hot enough to smell (luckily didn't burn due to 8A rateing.)

The 2 regs are completely seperate from each other except for inductive link in transformer... should I have it wired up diffirently?
currently 1 + 3 and 2 + 4 used with 1 and 3 tied to same point on respective bridges... i.e. I tried to make the halves the same....
  Reply With Quote
Old 18th March 2007, 10:26 PM   #2
Nordic is offline Nordic  South Africa
diyAudio Member
 
Nordic's Avatar
 
Join Date: Sep 2005
ok, found a wireing mistake... (traces not cut on stripboard)...
Now it doesn't overheat but each 12V reg is putting out 16V....

I Assume the regs are dead. right?
  Reply With Quote
Old 19th March 2007, 09:48 AM   #3
diyAudio Member
 
deduikertjes's Avatar
 
Join Date: Aug 2005
Quote:
I Assume the regs are dead. right?
Well, if voltage before reg = voltage after reg AND you didn't make another wiring mistake then the regs are dead

succes, Marco
  Reply With Quote
Old 19th March 2007, 10:25 AM   #4
Nordic is offline Nordic  South Africa
diyAudio Member
 
Nordic's Avatar
 
Join Date: Sep 2005
Thanks man, I noticed there was infact a voltage drop over the reg, after buying 4 new ones this morning I had the briight idea of replaceing the battery in my multimeter... was waaaaaay flat it seems... all is fine now, just getting the courage to make the final connection between PSU and amp now... will try one channel at a time I think.
  Reply With Quote
Old 20th March 2007, 08:34 AM   #5
diyAudio Member
 
deduikertjes's Avatar
 
Join Date: Aug 2005
Please do measure if there are any dead shorts in your amp between supply lines and earth...

Could save you some smoke.

And if you don't like the use of fuses in your supply lines then:

I like to add some small power resistors in the supply lines with a power which slightly above the expected power in these resistors.

Your nose will then tell if something is going wrong...

succes, MArco
  Reply With Quote

Reply


Hide this!Advertise here!

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
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
One transformer with 4 secondaries or two transformers with dual secondaries Baka Chip Amps 5 28th November 2008 06:39 AM
two single secondaries, two rectifier boards lm4780 kit gbolly Chip Amps 5 23rd August 2008 07:59 AM
Power supply FET's overheats in seconds - no load, why? valterdaw Car Audio 12 2nd July 2006 01:46 PM
Anybody heard about Tarzian Silicon Rectifier for Tube Rectifier Replacement? zxx123 Tubes / Valves 4 21st February 2005 04:02 AM


New To Site? Need Help?

All times are GMT. The time now is 12:52 PM.

Page generated in 0.07328 seconds (81.81% PHP - 18.19% MySQL) with 10 queries

Copyright ©1999-2012 diyAudio