Weird things with lm3886 (brainGT-kit) - diyAudio
Go Back   Home > Forums > Amplifiers > Chip Amps
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Chip Amps Amplifiers based on integrated circuits

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 11th June 2005, 11:04 PM   #1
diyAudio Member
Join Date: Mar 2005
Location: The Hague, the Netherlands
Default Weird things with lm3886 (brainGT-kit)

I just finished (at least that's what I thought I did..) an lm3886 BrianGT kit, but when I powered up I measured some strange values.
First of all, the power supply board makes 28VDC from 22VAC. Not exactly the 1.4 factor I was expecting.
Next, when I measured the DC offset, it was huge: about 1.6V on one channel and 1.7V on the other and the chips get very hot after running for some minutes without any load.

Any advice?
  Reply With Quote
Old 11th June 2005, 11:12 PM   #2
sss is offline sss  Israel
diyAudio Member
sss's Avatar
Join Date: Jul 2003
Location: Israel , haifa
Send a message via ICQ to sss
something is wring with your connections , dont power it up again u will burn the chip , show some pics if u can
if you are not living on the edge you are taking too much space
  Reply With Quote
Old 12th June 2005, 07:21 AM   #3
diyAudio Member
Join Date: Mar 2005
Location: The Hague, the Netherlands
Sorry, already took it apart. I've had it with those really stiff solid core silverized-copper (?) wires. Had to solder the - hard to reach - connections with the pcb's mounted in the case, that was just asking for bad connections.. Now I'll give it a go with some multi stranded wire and report back when I'm finished.
  Reply With Quote
Old 12th June 2005, 10:07 AM   #4
diyAudio Member
Join Date: Mar 2005
Location: The Hague, the Netherlands
Done! Now with DC offset 0.5 and 0.3 mV (not accounting for deviation of my 15 euro multimeter ). There was probably some shortage going on
  Reply With Quote
Old 14th January 2007, 03:58 PM   #5
diyAudio Member
Join Date: Feb 2004
Location: haifa
Send a message via ICQ to cozycactus
hi. where do you find electronic parts in haifa for diy?
  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
Things important to be said..helped by Mr. John Mateus to express things. destroyer X Solid State 22 31st July 2006 07:21 PM
WTB: Power Transformers For BrainGT Mono Block Kit jawbreak Swap Meet 1 2nd January 2005 06:26 PM
Correct Transformer BrainGT Kit? jawbreak Chip Amps 9 30th December 2004 08:02 AM
A few things.... Ziller Everything Else 11 9th January 2002 04:44 PM

New To Site? Need Help?

All times are GMT. The time now is 08:06 AM.

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