Arcam Alpha 5 no output - help - diyAudio
Go Back   Home > Forums > Source & Line > Digital Source

Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc.

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 6th September 2010, 12:45 PM   #1
diyAudio Member
 
Join Date: Jun 2008
Default Arcam Alpha 5 no output - help

Hi

My Alpha 5 is working, disc spinning, display and functions are OK but there is no sound.
The 4 regulators on the DAC board are cold, The SAA 7220 is hot.
Regulators on the mono board are hot.
It all seems normal.
I've lifted and re fitted the DAC board several times and still it's quiet.

No caps leaking, resistors burnt, no bangs as is often the case when I muck around with things.

Any tests or suggestions welcome.

Thanks

Andrew
  Reply With Quote
Old 6th September 2010, 04:44 PM   #2
Mooly is online now Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
Buzz the opamp inputs with a metal screwdriver for a quick easy test... keep the volume down on the amp. Is there any buzz or noise or not ?

Supplies OK to opamps ?

Muting OK, not on ?

Post a circuit and we'll have a look
__________________
-------------------------------------------------------
Installing and using LTspice. From beginner to advanced.
  Reply With Quote
Old 6th September 2010, 08:57 PM   #3
diyAudio Member
 
Join Date: Jun 2008
Mooly thanks

Do you mean literally ' poke ' the opamp legs with a screwdriver and listen for buzz ?

I also wouldn't know about the muting !
Where is that ? ( I hope it's not too obvious )

By the way, I forgot to mention....I recently transplanted the whole of the mono board and attached transport to another Alpha 5 case.....carefully of course and had no accidents along the way. The new case is much cleaner
and... damped - hence the motive for doing it.
Have I done something simple perhaps ?

Thanks for your suggestions

Andrew
  Reply With Quote
Old 6th September 2010, 10:00 PM   #4
diyAudio Member
 
Join Date: Jun 2008
Mooly

No buzzing from poked op amps !

Andrew
  Reply With Quote
Old 6th September 2010, 10:10 PM   #5
diyAudio Member
 
Join Date: Jun 2008
Mooly

No buzzing from poked op amps !

Andrew
  Reply With Quote
Old 6th September 2010, 11:02 PM   #6
diyAudio Member
 
Join Date: Jun 2008
Mooly Hi

Changed mono boards and it's back - all fine.

I must have damaged something on the original board.
So I fixed it but once again I don't know what or how.
I need to look at the board closely to see if there's anything obvious.

But hey, thanks for being there !
Regards

Andrew
  Reply With Quote
Old 6th September 2010, 11:11 PM   #7
diyAudio Moderator Emeritus
 
jean-paul's Avatar
 
Join Date: Sep 2002
Location: Germany
Hi, it has been a long time since I had such an Arcam but AFAIK the TDA dies in them. The SAA7220 becomes hot, this is normal for this chip.
__________________
It's only audio. Official member of the Norske Brillegeit Gang.
  Reply With Quote
Old 7th September 2010, 06:38 AM   #8
Mooly is online now Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
Just go through it carefully if you try it again.
__________________
-------------------------------------------------------
Installing and using LTspice. From beginner to advanced.
  Reply With Quote
Old 8th September 2010, 12:05 AM   #9
amc184 is offline amc184  New Zealand
diyAudio Member
 
amc184's Avatar
 
Join Date: May 2007
Location: Christchurch
Best thing to do in a case like this is to have a methodical look at the board with a 'scope. Something like:

- Are the power supply rails all present and correct?
- Does the digital bus into the SAA7220 look good?
- Does the digital bus from the SAA7220 into the TDA1541A look good?
- Does the analog output from the TDA1541A look good?
- Does the analog output from each OP27 look good?
- Does the analog output from each NE5534 look good?

The fact that both channels are not working makes me suspect that you won't get past item four. Once you've figured out which item above is the problem, it should be fairly straightforward to fix.
  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
ARCAM Alpha One weissi Digital Source 21 2nd October 2009 07:09 AM
Arcam Alpha 1 amplifier (30w) (TIP2955 / TIP3055 output stage) ash_dac Solid State 32 14th February 2009 04:43 AM
Arcam Alpha 5 - no output Tyron Digital Source 29 11th November 2008 10:10 PM
Output coupling caps in Arcam Alpha 5 CDP filholder Digital Source 6 23rd June 2005 01:28 PM
Arcam Alpha 5 + j baldam Digital Source 1 9th July 2003 10:20 PM


New To Site? Need Help?

All times are GMT. The time now is 06:40 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