Newsgroups: rec.audio.tech
Subject: Re: Ground Isolator for Digital Coax Line?
References: 
"Steve & Kathi Taylor"  writes:

> I have a ground loop problem of some kind causing noise between my SACD/DVD
> player and my receiver. I have traced the problem to the coaxial digital
> line between the two. Will a passive ground isolator -- a transformer --
> work on a digital line? 

If you are talking about digital line which carriet either S/PDIF or
AES/EBU digitla format, then a proper transformer will work for it. 

> Can someone recommend a reasonably priced one that might work? 

I do not have any specific transformer recommendation for this. 

A video isolation transformer (designed for composite video) 
could work I think, because it works at the same simpedances 
and frequency range as those digital audio signals 
(S/PDIF and AES/EBU on coax cable). I have not tested this myself.

A transformer designed only for the diigital audio could be 
a more economical solution if you can find such thing. 
A quite simple transformer will work for digital audio signals
(they have much smaller frequency range in them than vidoe signals).

Some information on S/PDIF interface transformers can be found at
http://www.epanorama.net/documents/audio/spdif.html
There are also information on building your own.



-- 
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at 
http://www.epanorama.net/