Alt-BEAM Archive
Message #00972
To: beam@corp.sgi.com
From: "Jarrell Clark" Jclark76@bellsouth.net
Date: Wed, 24 Feb 1999 21:55:57 -0000
Subject: [alt-beam] Re: Cadmium Sulphide Photocells.....
> -----Original Message-----
> From: owner-beam@corp.sgi.com [mailto:owner-beam@corp.sgi.com]On Behalf
> Of Robert McIntosh
> Sent: Thursday, February 25, 1999 12:05 AM
> To: beam@corp.sgi.com
> Subject: Re: Cadmium Sulphide Photocells.....
>
>
> Hendrickson wrote:
>
> > I think they are mostly used when photodiodes are hard to come
> by. They work
> > quite well, especially for biasing Nv nets. I haven't used them
> a lot, but it
> > seams to me that the "memory" effect of photoresistors would make them a
> > little inferior to PDs when used for photovore circuits.
>
> What do you mean 'memory effect'?
> Aren't photodiodes photovoltaic? Light dependant resistors aren't
> Rob.
LDRs tend to "work" with the amount of light. I built a light detector out
of LDRs(and other components, but that's really not relevent) Looked in a
toolbox it eventually would go off. Why there was a little light leakage and
the LDR adjusted down to that(which was waaaaaaaaay below the trigger level)
It took awhile to re-adjust to normal light. It would go crazy in a bright
room.
To test one you just hook up your meter leads and cover and uncover with
your hand. the value should change.
-_-_-_-_-_
PC ZEN
Yesterday it worked
Today it is not working
Windows is like that.
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