On Wed, 09 Sep 2009 20:55:49 +0200, Richard Rasker
wrote:

Jan Panteltje wrote:

On a sunny day (Wed, 09 Sep 2009 20:02:38 +0200) it happened Richard
Rasker wrote in
et:

So my question: is this a simple case of "bad luck", or are there other
ways a LED in an opto-isolator may fail in this weird way (current OK, yet
no light)?

Perhaps some part internal to the opto-isolater did break of due to
vibration and blocks the light path?
Did you open the defective one?

No, I didn't (yet) -- but isn't this very, very unlikely?

Richard Rasker

It's incredibly likely compared to what seems to be the only
alternative- an LED which acts exactly like a AlGaAs D but doesn't LE.

OTOH, an electrically damaged diode that measured something like a
short would not be unusual at all. Could be something like lightning
or RF damage. You don't have the opto in there because it's a benign
environment, eh?