Sigma 22+Dynalo reversed polarity accident. - diyAudio
Go Back   Home > Forums > Design & Build > Construction Tips
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Construction Tips Construction techniques and tips

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 21st July 2012, 12:17 PM   #1
diyAudio Member
Join Date: Feb 2012
Location: Riga
Default Sigma 22+Dynalo reversed polarity accident.

Today I finished my first big DIY project- Dynalo powered by a Sigma 22. While hastily troubleshooting a minor problem I accidentally wired the amp in reverse polarity. It didn't stay on for a long time (<6s) but still- it won't work and voltages for most points are all over the place.

Can someone please tell me what parts I should be expecting to replace? Both PCB's look intact and none of the electrolytic caps even went warm.
  Reply With Quote
Old 21st July 2012, 05:40 PM   #2
diyAudio Member
Join Date: Feb 2012
Location: Riga
So, it seems that current sources and the input stage have survived (phew!), however the whole output stage is toast.
  Reply With Quote
Old 23rd July 2012, 06:58 AM   #3
diyAudio Member
Join Date: Jul 2003
Location: Dona paula, Goa
Even if any transistors have survived, it is better u change all of them as u have wrongly biased.

Gajanan Phadte
  Reply With Quote
Old 23rd July 2012, 01:06 PM   #4
diyAudio Member
Join Date: Feb 2012
Location: Riga
Today I'll swap out all of the output BJT's and see what happens. According to my measurements probably some of them have even survived but I'm too lazy to check which ones.
  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
Reversed tweeter polarity martinbls Multi-Way 29 25th July 2011 06:46 AM
Help! I just fried a mini-Aleph (Polarity reversed) Russell Sit Pass Labs 0 10th December 2006 09:10 AM
reversed signal polarity? G_a_r_e_t_h Car Audio 19 14th September 2006 05:01 AM
Reversed polarity on Sprague Powerlytic starbase218 Solid State 11 23rd August 2006 12:53 PM
Blown amp (reversed polarity) tjmehta Car Audio 34 1st July 2006 04:20 AM

New To Site? Need Help?

All times are GMT. The time now is 08:00 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