Blown Rockford Fosgate 250M, help a newb =-) - diyAudio
Go Back   Home > Forums > General Interest > Car Audio

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 25th July 2009, 10:26 PM   #1
diyAudio Member
 
Join Date: Jul 2009
Default Blown Rockford Fosgate 250M, help a newb =-)

I work at a audio/detailing/tinting place, and in the electronics bay that had a few amps that were blown, and the RF 250m was one of them. But, I took the amp apart and found that the little black mosfet chip was blown. Well, one of them closest to the power and ground has a burn mark on it with some suit around it. I was wondering if I just replace that, if the amp should work again, or if there are other things that need to be checked.

When I was in there, I noticed a tiny surface mount resistor that was for some reason, not attached on one side. I just pushed it down, and resoldered it.

Please help me out. The RF guys are going to get me the correct shcematic monday, so I should be able to see what part numbers are on these circuits. Also, I am fairly good with a multimeter, so if you can just guide me threw this, I would appreciate it. I will attach a picture of the board so you can see what I am dealing with.
  Reply With Quote
Old 25th July 2009, 11:10 PM   #2
diyAudio Member
 
Join Date: Jul 2009
Here is a pic. How do you get the rest of the mosfet chip off?!
  Reply With Quote
Old 25th July 2009, 11:10 PM   #3
diyAudio Member
 
Join Date: Jul 2009
Here is another. This one, you can see the third resistor up the middle. That is the one that had come up on one side. I jsut pushed it back down, and resoldered it.
  Reply With Quote
Old 25th July 2009, 11:10 PM   #4
diyAudio Member
 
Join Date: Jul 2009
I dont think the pics were going to show because of them being too big. Here they are again.
  Reply With Quote
Old 25th July 2009, 11:10 PM   #5
diyAudio Member
 
Join Date: Jul 2009
The other.
  Reply With Quote
Old 25th July 2009, 11:11 PM   #6
Speakerholic
diyAudio Moderator
 
Cal Weldon's Avatar
 
Join Date: Jan 2004
Location: Near Vancouver
To post a pic click on the browse button at the bottom of the window.
__________________
Next stop: Margaritaville
Some of Cal's stuff | Cal Weldon Consulting
  Reply With Quote
Old 26th July 2009, 06:48 AM   #7
jaycee is offline jaycee  United Kingdom
diyAudio Member
 
Join Date: Apr 2004
Location: Norwich, UK
No pictures, but to answer your question, it is unlikely that replacing the blown mosfet will fix the amp. There will be further non-visible damage.
  Reply With Quote
Old 26th July 2009, 01:26 PM   #8
diyAudio Member
 
Join Date: Jul 2009
Try this again. How do I get the rest of that chip off?! lol
Attached Images
File Type: jpg optimized.p7250369.jpg (73.8 KB, 110 views)
  Reply With Quote
Old 26th July 2009, 01:27 PM   #9
diyAudio Member
 
Join Date: Jul 2009
Heres the other. The original pics I was trying to upload were too big. The resistor 3rd up from the bottom is the one that I pushed the one side back down, and resoldered it.
Attached Images
File Type: jpg optimized.p7250373.jpg (96.5 KB, 105 views)
  Reply With Quote
Old 26th July 2009, 02:12 PM   #10
diyAudio Member
 
Join Date: Mar 2007
To remove the rest of the transistor you will need a small butane torch. Lowe's sells a Bernzomatic brand torch and a small can of butane for under 20 dollars. You will also need some medium size Binder Clips available at Office Depot. The binder clips are required to keep the next component from separating from the thermal strup when you heat the component to be removed. Do not use a plumbing torch. As stated earlier there is probably something that caused the power supply transistor failure. Shorted output transistors are the most likely candidate for that. When the supply failed, it probably took out the gate resistors and possibly the pnp driver transistors that drive the FETs.
__________________
If it ain't broke Don't fix it
  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
Rockford Fosgate 325.1 phreaktor Swap Meet 1 28th February 2008 11:54 PM
Rockford Fosgate Power 800.4 lostamps Car Audio 6 2nd January 2008 12:21 PM
rockford fosgate 1000bd mike49504 Car Audio 48 17th May 2007 04:44 AM
rockford fosgate 500s mike49504 Car Audio 14 20th October 2006 06:04 PM
New Rockford Fosgate amp. $50.00 NerdMike Swap Meet 0 4th March 2005 11:57 PM


New To Site? Need Help?

All times are GMT. The time now is 06:39 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