There should be no destruction - the 1Mohm resistor will see to that.

John


"Paul VK3DIP" wrote in message
...
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.