Hi, Thanks everyone for the suggestions.
I tried putting 5 mA through it ( approx 1.6v forward voltage) and examining
it closely with a camera that I tested as being good at seeing IR and
nothing showed. I am leaning towards the high voltage theory of two series
silicon diodes in the one package. Anybody know a manufacturer of these
sorts of things or even what the package type is called?

Paul.

"Allodoxaphobia" wrote in message
...
On Sat, 31 Dec 2005 00:05:28 GMT, Paul VK3DIP wrote:
Hi all I recently purchased a bag of unmarked supposedly diodes and I am
snip
it is the top one
in this picture.
http://www.users.bigpond.com/pmcmahon/mysterydiode.jpg



Don't count it out as not being an LED. Some opaque-to-the-human-eye
packages are, in fact, quite clear in either the IR or UV range.
It could be an IR LED. (There's been many cases where light-sensitive,
'ordinary' diodes caused 'problems' in circuits on a well lit workbench.
The 'thing' would work one way in a buttoned-up case, and another way
under test.)

HTH
Jonesy
--
Marvin L Jones | jonz | W3DHJ | linux
Pueblo, Colorado | @ | Jonesy | OS/2 __
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