Re: Identifying a mystery diode

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" <e455gkf@xxxxxxxxxxx> wrote in message
news:dpj2vc$i4p$1@xxxxxxxxxxxxxxxxxxxxxxx
> Hi Paul,
>
> That sort of "mini-L" packaging is often used for vhf components, e.g.
> tuning diodes, hot carrier diodes and PIN diodes - and some of these have
> forward volt-drops of more than one volt.
>
> You can investigate that suggestion that it is a high-voltage rectifier by
> applying, say, 200v reverse voltage via a 1Mohm resistor and measuring the
> breakdown (if any) voltage of the diode, or what current flows. Any of the
> other suggestions - including mine - will break down.
>
> Are there definitely no markings?
>
>
> John A
> "Paul VK3DIP" <pmcmahon@xxxxxxxxxxx> wrote in message
> news:cXjtf.136133$V7.93540@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
>> 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
>>
>>
>>
>
>


.

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