NAD 304 Repairs - 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 27th July 2005, 12:16 PM   #1
diyAudio Member
 
Join Date: Jul 2005
Location: MK
Default NAD 304 Repairs

First post here.

I have a NAD 304 that i use for music while i try and finnish an amp based on a gainclone design. I turned this on yesterday to find the light was staying on red, and a smell of burning comming from it.

Searches have shown me that Some resistors should be changed, specificly R333 and R334 to 1 Watt. I have checked the resistors and they seem fine, but am about to change them anyway as i have some spare 1 watt resistors lying around.

are there any other idea's as to what is causing this - has anyone else experianced problems like this and it not been caused by the Resistors?

Thanks
  Reply With Quote
Old 27th July 2005, 02:18 PM   #2
diyAudio Member
 
Join Date: Jun 2005
Location: KL
Do u have the schematic diagram, I need to refer to it first bfore I can tell you anything.
  Reply With Quote
Old 27th July 2005, 02:57 PM   #3
Leolabs is offline Leolabs  Malaysia
diyAudio Member
 
Leolabs's Avatar
 
Join Date: Dec 2004
Location: Bukit Mertajam
Send a message via MSN to Leolabs
Where are those resistors located???
  Reply With Quote
Old 27th July 2005, 03:24 PM   #4
diyAudio Member
 
Join Date: Jul 2005
Location: MK
UPDATE:

have replaced resistors, it still isn't turning green. any other ideas?
  Reply With Quote
Old 27th July 2005, 03:24 PM   #5
diyAudio Member
 
Join Date: Jul 2005
Location: MK
I am afraid not.

I am still trying to find something visably damaged, but it dosn't seem to be that easy. my searches showed me a few people had the diagram, so im going to try and email them to get it
  Reply With Quote
Old 27th July 2005, 04:07 PM   #6
diyAudio Member
 
Join Date: Jun 2005
Location: KL
I'm not able to help you since you only give me very little detail. But I can tell you that your NAD 304 protected mostly some components malfunction or spoiled. You better check that whether the transistors is still in good condition or not, then check v+ and v- voltage.
  Reply With Quote
Old 27th July 2005, 06:26 PM   #7
diyAudio Member
 
Join Date: Jul 2005
Location: MK
Thanks for your help so far, if there is any infomation you need please just ask - i will try to help as much as i can.

I have no idea what part of the circuit is damaged, i would assume it is not the powersupply or the LED would not light up at all. But other then that i have no idea.

I noticed a Fuse has slipped partly out of it's holder, as the amp worked last time it was on, could the damage be from the amp being dropped, i am guessing i should try re soldering all the joints?

Leolabs: The resistors are located neer the main transistors and heatsink. There are also a second pair that seem to be part of the pre amp which are supposed to be replaced if they are not 1 Watt items, i have checked both and they are the correct values.
  Reply With Quote
Old 28th July 2005, 11:14 AM   #8
diyAudio Member
 
Join Date: Jul 2005
Location: MK
I have obtained and uploaded the schematic here
  Reply With Quote
Old 28th July 2005, 04:51 PM   #9
diyAudio Member
 
Join Date: Jun 2005
Location: KL
I think you need to check whether there is any voltage go into the pre-amp and power amp board. Because last time my friend were using NAD amp also and faced the same problem, but he finally found out that there is no supply voltage to the power amp.
  Reply With Quote
Old 28th July 2005, 08:29 PM   #10
diyAudio Member
 
Join Date: Jul 2005
Location: MK
Okay, the NAD 304 is capable of being bridged - would i be able to check if the pre amp is producing any power by checking this connection in relation to the phono ground?
  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
Speaker repairs graeme uk Multi-Way 7 24th November 2008 10:04 PM
Helix repairs? thxdave Car Audio 0 10th February 2007 08:40 PM
speaker repairs onlinejames Multi-Way 1 20th September 2006 07:50 AM
Major PCB repairs cm961 Parts 6 18th January 2003 12:37 PM


New To Site? Need Help?

All times are GMT. The time now is 01:04 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