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78RPM
User Rank
Platinum
Would a constant current source help?
78RPM   10/16/2012 10:38:46 AM
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It's impossible to read the documentation but I'm responding to your problem with inconsistent linearity of photocells.  Yes, photocells are imprecise and non-linear. Much of the voltage appears across the limiting resistor. Consider putting a transistor as a constant current source in series with photocells, eliminating the resistor. The voltage across the transistor will be a consistent two diode drops. That way, all the voltage change appears across the photocell. I hope I have understood your problem.

johnmoran
User Rank
Silver
Instructions ...
johnmoran   1/20/2012 10:03:15 AM
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Hello

You may be an engineering student but your instruction writing skills are appalling - please try to get all the images the same size, then people may be able to read them.

John



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