chuck wrote in news:1153748524_106745
@sp6iad.superfeed.net:

Using a Keithley
electrometer, I measured a forward
current of about 10 microamps at a
voltage of 300 mV, consistent with the
675 mV/100 mA measurement.


At this level, a lot of what the Keithley is measuring is the diode's own
generated voltage. Hook the Keithley to a silicon diode sitting on the
bench, not attached to anything. Depending on how hot it is (and how close
to any radioactivity it is), there's always a junction voltage from the
thermionic emission of the junction, itself.

Got a hot radioactive source around? Keep the Keithley across the diode
and move the diode up against any beta or gamma sources and watch it fly...
(c;

(Depleted uranium bullets are great for this experiment. They're free in
Afghanistan and Iraq...)

Which Keithley is it? I used to repair and cal them at the Metrology
Laboratory of the Quality Assurance Office, Charleston Naval Shipyard (Code
132)...may she rest in peace.