Testing amp shut down - Page 2 - diyAudio
Go Back   Home > Forums > Amplifiers > Chip Amps

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
Reply
 
Thread Tools Search this Thread
Old 18th August 2011, 06:50 PM   #11
Mooly is online now Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
No fluids in FET's

Piccys a bit blurry so can't see but baked heatsink compound sounds favourite.
__________________
-------------------------------------------------------
A simulation free zone. Design it, build it, test it.
  Reply With Quote
Old 18th August 2011, 06:56 PM   #12
diyAudio Member
 
Join Date: Apr 2005
Location: Simcoe Ont
I am hoping for a short cut here. Would it be worth the time to clean and reapply thermal compound or is the FET likely shorted internally
?
  Reply With Quote
Old 19th August 2011, 06:09 AM   #13
Mooly is online now Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
If the FET were shorted it wouldn't work at all.

tbh I think you are going to struggle with this. You would need to know first hand how what the amp is driving, how hot its getting etc. Does this fan/s cut in correctly ? Have you seen them run.

It sounds as though the amp is shutting down in response to some overload sensing circuitry...
__________________
-------------------------------------------------------
A simulation free zone. Design it, build it, test it.
  Reply With Quote
Old 19th August 2011, 06:56 AM   #14
diyAudio Member
 
digits's Avatar
 
Join Date: Apr 2011
...or plainly being driven too hard too long. Don't believe everything you read on the box. That brown suff just looks like glue or varnish or something.
  Reply With Quote
Old 19th August 2011, 12:40 PM   #15
diyAudio Member
 
Join Date: Apr 2005
Location: Simcoe Ont
When the amp turns on, the fan is slow. At about 15 seconds it is running faster. At about 45 seconds, fan is running full speed. I have not been able to make it shut down.
  Reply With Quote
Old 19th August 2011, 04:21 PM   #16
diyAudio Member
 
Join Date: Apr 2005
Location: Simcoe Ont
OOPS. I am not sure what happened!
I cleaned surfaces and replaced output ICs
When I turned it on, it seemed to be running fine. Fan was running at normal speed.
There was a small spark yet everything seemed fine.
I plugged a speaker in and got a full 60hz hum. Maybe cooked speaker but that's OK
Feeling discouraged but not ready to back down.
  Reply With Quote
Old 19th August 2011, 05:09 PM   #17
johnr66 is offline johnr66  United States
diyAudio Member
 
Join Date: Mar 2009
I would have wagered that there was nothing wrong with the amp to begin with. Probably just overloaded by a "friend" who doesn't know any better. Now this amp that worked fine is broken to be sure!

I don't mean to be rude but your in too deep. Take the thing in and have it serviced by a professional. Unless, of course, your friend doesn't mind you using it as a learning tool.
  Reply With Quote
Old 19th August 2011, 06:08 PM   #18
diyAudio Member
 
Join Date: Apr 2005
Location: Simcoe Ont
I will never improve my skills by taking it to be serviced. Just need some help along the way
There was definitely something wrong with the amp. 30 seconds of operation and it was running fan full speed.
I have replaced the ICs perfectly with brand new direct replacements not a drop of excess solder.
New ICs are doing something that the old ones didn't do.
Now I am hoping to find out what that is.
There is more skill, knowledge and experience on this forum than in most service centers.
Unfortunately I don't have it!
Thanks

Last edited by argonrepublic; 19th August 2011 at 06:15 PM. Reason: corrections
  Reply With Quote

Reply


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
Amp Guts Shut Down? amc32 Car Audio 4 15th September 2009 04:01 AM
UcD amp cant shut off by pulling the tail current zilog Class D 1 5th April 2006 01:05 PM
Please Help - amp pop, shut down bonz Solid State 1 30th April 2005 11:08 PM
x-over makes my amp get hot and shut down SimontY Solid State 10 16th April 2004 04:00 PM
Adcom Amp "Whines" when shut off Whell Solid State 11 1st April 2004 03:34 AM


New To Site? Need Help?

All times are GMT. The time now is 11:45 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2