Alt-BEAM Archive

Message #13373



To: beam@sgiblab.sgi.com
From: Bruce Robinson Bruce_Robinson@telus.net
Date: Wed, 12 Apr 2000 11:52:30 -0700
Subject: Re: Photodiode use in BEAM circuits


"Dr. Duncan Lawrence" wrote:
>
> ... can the photodiodes be swapped for Light Dependant Resistors
> in either application?

Yes, but ...

When the pair of photodiodes receive different amounts of light, there
will be a bias towards one side of the circuit. A straight substitution
of LDRs would influence both sides of the circuit equally, so the effect
would be quite different.

To use LDRs, you would need to put them in parallel with each other, and
add a pair of diodes, one in series with each LDR. Kind of like this:

+--- LDR ---|<---+
| |
--+--->|--- LDR ---+--

Regards,
Bruce



13374 Wed, 12 Apr 2000 15:09:57 EDT Web Page... beam@sgiblab.sgi.com beam@sgiblab.sgi.com I'd like to start my own web page about BEAM soon, and I was wondering
what's the best web site host? Thanks!
Rusty



13375 Wed, 12 Apr 2000 17:01:03 -0400 Web Page...
> I'd like to start my own web page about BEAM soon, and I was wondering
> what's the best web site host? Thanks!
> Rusty
>


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