I tried this and found that it works on some and not on others. It DIDN'T
work on a PN2222A (shows zero, and VERY close to it, not even a few mV
difference as I connected and disconnected the emitter) but DID on a
2N4401. Any idea why? I would have thought that the base junction was thin
enough in all cases to easily pass the light from the EB to the BC junction.

I like this demonstration very much. My initial guess was that it WAS going
to be about 0.6V negative,and due to carrier tunneling, but I realize that
I was wrong and I like the photonic explanation a lot!

BTW, any tips on removing the metal cover from a metal can transistor? I'd
like to see it act as an LED. What color light does it produce (My
guess=red)? If you go by the voltage drop (about 5v) it should be UV,but I
realize that is probably not the case,and that the voltage drop is really
made up of many avalanche scatterings of lower potential.

Sean

At 09:00 AM 7/4/99 -0700, you wrote:
>At 11:21 PM 7/4/99 +1200, you wrote:
>>Y' canna break the laws of Physics :-) / DO try this at home:
>
>If you use a metal transistor you can open the case and _SEE_ what happens.
>
>The reverse-biased junction produces light, and it causes the other
>junction to produce electricity(all those junctions are silicon solar
>cells, after all!).
>
>I doubt if your spice models account for this.
>
>:-)
>
>-Bob
>
>http://www.bobblick.com/
>
|
| Sean Breheny
| Amateur Radio Callsign: KA3YXM
| Electrical Engineering Student
\--------------=----------------
Save lives, please look at http://www.all.org
Personal page: http://www.people.cornell.edu/pages/shb7
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