41hz Amp10 Basic Setup Issues - diyAudio
Go Back   Home > Forums > Amplifiers > Class D

Class D Switching Power Amplifiers and Power D/A conversion

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 15th March 2008, 07:01 PM   #1
diyAudio Member
 
raromachine's Avatar
 
Join Date: Jun 2006
Default 41hz Amp10 Basic Setup Issues

Apologies for posting here and not on the 41hz forum - I can't seem to register there and I know folk here are pretty knowledgable.

I've soldered up an amp10 - which apart from a small short in the PCB at one edge (which I've now fixed) - seems to be running, but not quite right.

My 5V+ gives exactly 5V+, my 18VAC feeds become about 2x25.5V which is right as far as I can see.

The LED which signal whether the AMP is muted or un-muted glows very dimly sometimes just after switching on or off. The other LED that shows whether the speaker-relay is open or closed seems to work perfectly. I've checked all the of the R values around the LEDs and these seem fine - though it appears the muting LED/control is driven from the Tripath chip.

The speaker terminals have a DC offset of 2.5v when measured on my autoranging meter - which is crazy high in my estimation.

No input signal or output driver is connected - and I've checked the board from shorts repeatedly!

Any ideas what could be going awry?

Cheers,
raro
  Reply With Quote
Old 15th March 2008, 07:24 PM   #2
diyAudio Member
 
raromachine's Avatar
 
Join Date: Jun 2006
Pics:

Click the image to open in full size.

Click the image to open in full size.
  Reply With Quote
Old 15th March 2008, 09:40 PM   #3
diyAudio Member
 
nicoch58's Avatar
 
Join Date: Oct 2004
short the input and try trimmer for dc offset .... max 70mv if not chip are burn , put a 1000uf to work around dc offset but......recheck all
__________________
Sic58
  Reply With Quote
Old 15th March 2008, 10:08 PM   #4
diyAudio Member
 
mazdapowered's Avatar
 
Join Date: Jan 2006
Location: UK
I don't have the BOM to double check but there is a resistor missing, right next to "41hz" written on the board, which I have seen fitted on another AMP10 basic.
__________________
Richard
  Reply With Quote
Old 15th March 2008, 10:25 PM   #5
diyAudio Member
 
raromachine's Avatar
 
Join Date: Jun 2006
Quote:
Originally posted by mazdapowered
I don't have the BOM to double check but there is a resistor missing, right next to "41hz" written on the board, which I have seen fitted on another AMP10 basic.
It's on the bottom - the holes deformed after I removed the resister for the 3rd time - took me a while to realised the BOM for Amp10 and Amp10 Basic were different.

If it wasn't there neither of the LEDs would work.

I've actually found a post on the 41hz forums that practically duplicates my issues:

http://www.41hz.com/forums/topic.asp?TOPIC_ID=1763

I think I'll give this a whirl
  Reply With Quote
Old 15th March 2008, 11:59 PM   #6
diyAudio Member
 
raromachine's Avatar
 
Join Date: Jun 2006
A bit of desoldering, the destruction of another via and a 1.5K resistor (I had no 1K) later and I'm in business - offset trimmed to a 1mV and stable. Now I just need to buy some speakers to test the amp with
  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
41Hz AMP10, Need Advice nfm Class D 12 3rd November 2008 01:30 PM
Amp10 Basic Transformer suggestion vaughn Class D 6 16th August 2008 09:31 PM
[FS] Assembled 41HZ AMP10 for sale! Sander Swap Meet 0 25th March 2008 09:40 PM
Using an SMPS with Amp10 Basic? raromachine Class D 9 19th December 2007 11:37 PM
41hz Amp10 for Sale Peter Menting Swap Meet 4 3rd September 2007 06:34 PM


New To Site? Need Help?

All times are GMT. The time now is 06:15 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