Go Back   Home > Forums > Live Sound > Instruments and Amps

Instruments and Amps Everything that makes music, Especially including instrument amps.

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 10th July 2008, 05:43 PM   #1
diyAudio Member
 
Join Date: Jul 2008
Default Peavey Roadmaster help

Last night at my bands practice my '75 Peavey Roadmaster was in standby mode and just started smoking and smelling pretty bad. It was fine all practice and all the tubes were still lit up. I turned it off right when I noticed so but im sure that it doesnt work anymore. I have attached a schematic. Any ideas on what might have happened? Im not to familiar with audio amps as I have only had expierience working with RF tube and transistor amps.
Thanks
Jeff
Click the image to open in full size.
  Reply With Quote
Old 12th July 2008, 06:38 PM   #2
diyAudio Member
 
Join Date: Jul 2005
Location: North Derbyshire
First thing to do is look inside and see what's been smoking, components smoking is a really good clue to what's happened.

So see if you can find what it was, and tell us the component number.
__________________
Nigel Goodwin
  Reply With Quote
Old 13th July 2008, 11:48 PM   #3
diyAudio Member
 
unclejed613's Avatar
 
Join Date: Dec 2006
if it smells really bad, its probably the output transformer. pro-audio techs call it "the smell of death". if it smelled like fish oil, it's probably an electrolytic cap, which is one of the most vigorous producers of smoke when they go bad. they look like small aluminum cans. look inside to see if any of them are bulged, or have the shrink label melted. after that comes burned components like resistors and diodes.
__________________
Vintage Audio and Pro-Audio repair ampz(removethis)@sohonet.net
spammer trap: spammers must die
  Reply With Quote
Old 19th July 2008, 05:22 AM   #4
Enzo is offline Enzo  United States
diyAudio Member
 
Join Date: Sep 2004
Location: Lansing, Michigan
Power is not supplied to the output transformer in standby mode. That would make it seem less likely to smoke in standby.

Bassen, if you can handle RF tube circuits and SS amplifiers, I can't imagine why you couldn't troubeshoot this circuit.
  Reply With Quote
Old 20th July 2008, 03:56 AM   #5
diyAudio Member
 
unclejed613's Avatar
 
Join Date: Dec 2006
i tried magnifying the schematic with irfanview to see what power supply rail went to what part of the circuit. i can identify the screen supply and the plate supply easily enough, but where does the rail from the bridge rectifier go to?
__________________
Vintage Audio and Pro-Audio repair ampz(removethis)@sohonet.net
spammer trap: spammers must die
  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
peavey amp fellowesman Solid State 23 13th August 2011 02:25 AM
Peavey 1.3k 406vette Solid State 7 30th August 2008 01:45 PM
Help for my Peavey PV8.5C fabiodord Solid State 17 8th June 2008 08:29 PM
peavey fellowesman Solid State 10 22nd April 2006 06:55 PM
Peavey Cs-800 Pwr. Amp dstx144 Solid State 10 30th January 2006 04:16 PM


New To Site? Need Help?

All times are GMT. The time now is 04:02 PM.


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