audiolab 8000a resistors - 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 5th October 2007, 09:31 PM   #1
dazsti is offline dazsti  United Kingdom
diyAudio Member
 
Join Date: Oct 2007
Default audiolab 8000a resistors

hi everyone, ive done a search and come up with a few bits and bobs,but im a bit of a noob at diy audio so here goes-shorted my speakers -blown fuse in audiolab 8000a,replaced fuse- blows again,took lid of noticed 7 resistors burnt out,see pic-Click the image to open in full size.
- so i took resistors out to look for colour codes, but the resistors are all burnt black like my wifes toast, so i ask does anybody know the values of the resistors marked in pic eg:R747=560 ohm???thankyou for any replies, if i cant fix it i will have to send it to the rubbish tip-nah only kidding- kev green at audiocellar !
  Reply With Quote
Old 5th October 2007, 10:15 PM   #2
Bigred is offline Bigred  Canada
diyAudio Member
 
Join Date: Jul 2007
The best I can do is provide a schematic without the corresponding board numbers. You will have to follow the traces to some of the knowns from the schematic. A little more effort but works. The diodes and transistors are actually listed on the board as what they are D813=1N4002 for example.

EDIT: Come to think of it, the values of the resistors are what the number on the board is also. R743=looks to be 330ohm and R946=47ohm for example.
Attached Images
File Type: jpg audiolab8000a.jpg (55.4 KB, 381 views)
  Reply With Quote
Old 5th October 2007, 10:51 PM   #3
diyAudio Member
 
Join Date: Jul 2007
hi,
it is very clear that the part value of the component is listed on the board, resistor 47 ohms, diode and so on is already there on pcb.
  Reply With Quote
Old 5th October 2007, 10:54 PM   #4
Bigred is offline Bigred  Canada
diyAudio Member
 
Join Date: Jul 2007
Quote:
Originally posted by rohms
hi,
it is very clear that the part value of the component is listed on the board, resistor 47 ohms, diode and so on is already there on pcb.
Yes all but the ones that got blown off It was covered already
  Reply With Quote
Old 5th October 2007, 11:03 PM   #5
tvi is offline tvi  Australia
diyAudio Member
 
tvi's Avatar
 
Join Date: Apr 2001
Location: Moonee Ponds, Vic, Australia
R743 330R
R747 47R
R935 470R?
R847 470R

another R847 ? 47R
D813 1N4002
R946 47R

The values are written on the board.
You can also compare one channel to the other.

Regards
Jaames
__________________
The small part of ignorance that we arrange and classify we give the name of knowledge.
Ambrose Bierce
  Reply With Quote
Old 6th October 2007, 02:20 AM   #6
dazsti is offline dazsti  United Kingdom
diyAudio Member
 
Join Date: Oct 2007
Default LAST ONE ????

thanks for your replies,everyone-i get it now see revised pic-should have realized they were correct values on board -still leaves me with one unknown R935????-miniture atom bomb schorched the text and i cant read it!

Click the image to open in full size.

any help very much appriciated again thanks darren
  Reply With Quote
Old 6th October 2007, 02:47 AM   #7
Bigred is offline Bigred  Canada
diyAudio Member
 
Join Date: Jul 2007
Thats why I told you that your going to have to follow the traces to some of the knowns and figure out the values from the schematic. It shouldn't be too difficult to map out.
  Reply With Quote
Old 6th October 2007, 09:06 AM   #8
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Hi,
if the resistors are blown there could also be damage to the traces feeding those resistors.
There will definately be damaged transistors that caused the resistors to blow.
I wonder why the protection did not operate?
Sometime odd here.
Has the board been altered or the fuses changed for the wrong values or the wrong speakers attached or duff cables/duff fingers been poking around? Or something spilled inside?

BTW,
this is a stereo board, the good side should match the damaged side. Compare one to the other.
__________________
regards Andrew T.
  Reply With Quote
Old 6th October 2007, 10:04 AM   #9
Did it Himself
diyAudio Member
 
richie00boy's Avatar
 
Join Date: Nov 2003
Location: Gloucestershire, England, UK
As Andrew said, change the output transistors and drivers, they will be partially damaged if not completely blown.
__________________
www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, kits and more.
  Reply With Quote
Old 12th August 2008, 08:35 PM   #10
Kajman is offline Kajman  United Kingdom
diyAudio Member
 
Join Date: Jan 2006
Location: WILTSHIRE
I have finally fixed my audiolab 8000A without too much work in the end. I just had to be patient as the problem was not obvious. The protection circuit had fried components which i replaced. I still had not solved the problem as I was getting no output and the two 470R resistors in the protection circuit were heating up very badly. You will also notice that the relay does not click. The problem was still in the power amp section. All the transistors tested fine but just check for another short component on the side that fried the protection circuit. Mine is up and running and the cost was next to nothing as no transistor in the power amp needed replacing despite the protection circuit components being completely fried. Patience pays
  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
Audiolab 8000a dantzig65 Solid State 9 6th June 2011 02:48 PM
Modifying Audiolab 8000A RichLund Solid State 12 29th October 2009 07:32 PM
Audiolab 8000a fuse badnote Solid State 2 14th May 2009 01:57 PM
Help! Audiolab 8000A Matthewong Solid State 9 15th October 2007 06:09 PM
audiolab 8000a davephot Solid State 35 26th November 2006 10:25 PM


New To Site? Need Help?

All times are GMT. The time now is 12:56 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