In article ,
John Smith I wrote:

Mike Chambers wrote:
...

Mike:

Here is an interesting link:

http://www.waypoint.com/users/~disco...esentation.htm

One circuit I seen on this page makes use of an opto-isolator. Seems to
me that with a led and photo-transistor one could kludge together a unit
which would seem to perform miracles!!!

The OP already tried a isolation transformer so I don't think an
opto-isolator will be any more helpful.

I expect that it is a common mode noise issue. He can buy common mode
chokes that just clamp on the cables to find out.

--
Telamon
Ventura, California

Telamon wrote:
...
The OP already tried a isolation transformer so I don't think an
opto-isolator will be any more helpful.

I expect that it is a common mode noise issue. He can buy common mode
chokes that just clamp on the cables to find out.


Surely you jest, with optical isolation, there is NO direct connection ...

Unless you are proposing the rf is able to transverse the light beam.

JS

John Smith I wrote:

Surely you jest, with optical isolation, there is NO direct connection ...

Unless you are proposing the rf is able to transverse the light beam.

JS

The optoisolators are only used for ptt keying, not for the audio. The
audio is usually isolated with transformers. But, just because the op
has tried transformers, doesn't necessarily mean he did it correctly.

Brad.