John,
Thanks for the suggestion, I've got a thousand of the things so I have no
problems testing one or two to destruction. However it might take a little
while to rig up a power supply etc., I will give it a go and get back to the
group. No there are no markings at all, not even an indication of a band or
dot to mark the cathode. I too thought they looked like a rf package which
is why I bought them.

Paul.

"John A" wrote in message
...
Hi Paul,

That sort of "mini-L" packaging is often used for vhf components, e.g.
tuning diodes, hot carrier diodes and PIN diodes - and some of these have
forward volt-drops of more than one volt.

You can investigate that suggestion that it is a high-voltage rectifier by
applying, say, 200v reverse voltage via a 1Mohm resistor and measuring the
breakdown (if any) voltage of the diode, or what current flows. Any of the
other suggestions - including mine - will break down.

Are there definitely no markings?


John A
"Paul VK3DIP" wrote in message
...
Hi all I recently purchased a bag of unmarked supposedly diodes and I am
trying to figure out what they are. The clues so far are normal diode
action on a multimeter (ie conducts one way but not the other) but the
forward voltage is high at about 1.4 - 1.5 volts. The packaging is a
small
square black plastic box with flat axial leads one of which has a small
cross
piece on it. This packaging suggests small signal or at least low power.

If anyone wants to look at the mystery diode it is the top one
in this picture.
http://www.users.bigpond.com/pmcmahon/mysterydiode.jpg
The bottom one is a normal glass 1N914 just for scale.

There is nowhere for the light to come out (or in) so they are not LEDs
which is the only other diode like component I have come across with that
high a forward voltage. Could it be two silicon diodes in series?

Any suggestions or even just identifying the case outline would be
appreciated.

Thanks
Paul VK3DIP