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

Class D Switching Power Amplifiers and Power D/A conversion

Looking for MTX 421D info
Looking for MTX 421D info
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 21st September 2009, 12:30 AM   #1
brandes.cm is offline brandes.cm  United States
diyAudio Member
 
Join Date: Sep 2009
Location: Wisconsin
Default Looking for MTX 421D info

I have a 421D amp that has full +DC rail voltage on the speaker output terminals. C143, C140 and C120 all showed signs of damage, C120 was completey fried. One of the output fets was also shorted. Any ideas on where to start with this?

I wasn't able to find any schematics for MTX amps anywhere, apparently they won't release them. Attached is a pic of the PCB, where is the saw waveform produced?

Any info would be appreciated.
Attached Images
File Type: jpg DSCN0730.jpg (970.3 KB, 56 views)
  Reply With Quote
Old 23rd September 2009, 04:20 PM   #2
lee1976 is offline lee1976  Poland
diyAudio Member
 
Join Date: May 2009
Location: 52.740N, 15.230E
The diagram can be a problem, but I would start from checking the output transistors because probably be pierced
Subsequently, the capacitors, which you write and you can see in the picture and check transistors control (driver)

Regards
  Reply With Quote

Reply


Looking for MTX 421D infoHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Need info on my Onkyo, can't find any info anywhere. gixxierific Digital Source 0 19th April 2009 03:49 PM
How to get cathode bias info from grid bias info? leadbelly Tubes / Valves 8 14th August 2008 04:40 PM
MTX Thunder 421D spooney Car Audio 5 19th April 2008 03:40 AM
MTX Thunder 421D.Plays fine at times but occasionally blows a fuse?Input appreciated spooney Car Audio 2 13th June 2007 10:59 AM
mtx 421d amp catchuk Car Audio 1 5th February 2004 10:20 PM


New To Site? Need Help?

All times are GMT. The time now is 09:50 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio
Wiki