Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!hc!lll-winken!uunet!unisoft!hoptoad!dasys1!aj-mberg
From: aj-mberg@dasys1.UUCP (Micha Berger)
Newsgroups: sci.electronics
Subject: Re: Light Duration Meter
Summary: Integrator
Message-ID: <9318@dasys1.UUCP>
Date: 12 Apr 89 12:19:16 GMT
References: <102@raider.MFEE.TN.US>
Organization: The Big Electric Cat
Lines: 17

Bob Reineri writes:

> I do have one idea: Perhaps a solar cell, connected thru an RC network, that
> would charge up a capacitor to a given voltage, depending on the amount of
> sunlight received over the course of a day. Then I could somehow measure the 
> charge on the cap at the end of the day. Just a thought....

Here's my 2 cents. Use an op-amp integrator to integrate instead
of the capacitor.  Have a photocell as the input voltage to be integrated.
This way, at the end of the day all you gotto do is read the voltmeter at
the integrator's output, and hit a reset button. The only thing I haven't
I haven't figured out is calibration.
-- 
					Micha Berger				     
Disclaimer: All opinions expressed here are my own. The spelling, noone's.
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