Problem with 100W Audio Amplifier!? - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 20th July 2011, 12:25 PM   #1
radio is offline radio  Macedonia
Banned
 
Join Date: Oct 2009
Location: Bitola MACEDONIA
Red face Problem with 100W Audio Amplifier!?

Hello all!
I made the schematic (circuit) given amplifier shown below. Worked great for almost half a year. The other day broke down ... the output is DC-offset voltage of about 24Vdc (supply voltage amplifier is Us = + /-37Vdc) i replaced the transistors T1, T2, T3 and T4 with the new re DC-offset voltage at the output about 24Vdc. How to resolve the problem?
When the amplifier was the correct voltage to the middle trimmer P1 statement with the mass was 0.7 V and now is about 24Vdc.
Thanks

See Figure (circuit) !!
Attached Files
File Type: pdf Slika 1.pdf (92.7 KB, 115 views)
  Reply With Quote
Old 20th July 2011, 12:58 PM   #2
Banned
 
Join Date: Jan 2005
Again another Elektor design. Avoid these!!! Instead look at the tried and proven designs here on diyaudio like Destroyer X's Blame series, quasi's quasi mosfet amp, Apex's quasi amp for beginners and such.
  Reply With Quote
Old 20th July 2011, 05:48 PM   #3
diyAudio Member
 
east electronics's Avatar
 
Join Date: Jan 2006
Location: Athens GREECE
you need to find out if you have +24 or -24
you need to remove the VI limiter transistor ( T 9 ) of the lower rail it could be also leacky to see how it will go
then again you need to replace if leacky T5 vas amplifier
------------------------------------------------------------------------------------

intersting though around this circuit ( also never presented before in the forum ) is the VI limmiter and especially since active directly in the output and senses both V and I ... normally VI limmiters are working on the drivers and not in the output

Dear Tekko ( with fancy signature ) i know you hate hate hate VI limmiters but for fun this might be quiet interesting in the quasi threads ...

( its too hot in Greece now days 40-42 so i hope i am allowed to make a joke from time to time )

happy regards
sakis
__________________
SERVICE ΕΝΙΣΧΥΤΩΝ ΚΑΙ ΙΑΠΩΝΙΚΩΝ ΜΗΧΑΝΗΜΑΤΩΝ ΗΧΟΥ www.eastelectronics.gr
  Reply With Quote
Old 20th July 2011, 07:17 PM   #4
radio is offline radio  Macedonia
Banned
 
Join Date: Oct 2009
Location: Bitola MACEDONIA
Quote:
Originally Posted by Tekko View Post
Again another Elektor design. Avoid these!!! Instead look at the tried and proven designs here on diyaudio like Destroyer X's Blame series, quasi's quasi mosfet amp, Apex's quasi amp for beginners and such.
Oh,..... this is my design combined from other amplifiers!!
The problem was the resistor R14 !!?
Otherwise, this amplifier great playing!!
cheers

Last edited by radio; 20th July 2011 at 07:26 PM.
  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
I tried the ebay MX50 DIY Kit, Class AB 100W+100W; Worked but problem. Buckeye Solid State 61 15th August 2014 03:20 PM
Maplin 100W mosfet amplifier - power supply problem HBrunt Solid State 32 3rd December 2013 07:11 AM
JL audio 1000/1 amplifier problem jz23 Car Audio 1 6th April 2007 05:50 AM
Samson F800 Audio Amplifier Problem gooofy Solid State 0 6th March 2007 02:30 PM
ESP Project 3A - 60-100W Hi-Fi Amplifier Problem and need helps bugbite2k Solid State 18 31st December 2004 01:18 PM


New To Site? Need Help?

All times are GMT. The time now is 06:42 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