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Old 03-27-2012, 01:56 AM
Rinehart Rinehart is offline
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Selenium and the photoconductive effect

This might not be in the right forum, but I have a couple of questions regarding the discovery of the photoconductive properties of selenium.
I have read that in 1873 Willoughby Smith was using rods of selenium in checking underwater telegraph cables when he noticed the electrical resistance changed when they were exposed to light. Does anyone know how these rods were used exactly to check underwater cable? Also, from what I can gather, this appears not to have been a new method, so why didn't anyone notice it before?
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Old 03-28-2012, 10:30 AM
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Old 03-29-2012, 12:26 AM
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Not today it isn't. The page wouldn't display.
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Old 06-21-2012, 08:43 PM
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When I was in high school, selenium rectifiers were fun when you exceeded their ratings...
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Old 06-22-2012, 06:29 PM
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Smelly too, I'd imagine....
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