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how to replace a potentiometer by a photocell ? ? Answered

in the diagram, two pins of the pot are connected to resistors on each side and the third (variable) to the power source. That makes three connections and the photocell has only two!?

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metal slug 2 (author)2009-09-01

I know just the thing which may help you. Read this: http://www.societyofrobots.com/schematics_photoresistor.shtml
When I was first building the $50 robot (found on the above mentioned site), the same thing confused me.

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steveastrouk (author)2009-07-03

I can't see a diagram. Can anyone else ? Steve

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marcia09 (author)steveastrouk2009-07-28

it is because there is no diagram. I´m sorry, English not being my language, i wrote badly. I apologize. The thing is, I found a diagram I want to experiment and it says the potentiometer can be replaced by a photo-resistor. But on the diagram, the potentiometer has two resistors on each side and the voltage connected to it perpendicularly. So how can I do that with a photo-resistor that has only two legs?

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OnlyUsernameAvailable (author)2009-07-03

You may have poor results with the difference in resistance between the pot and the photoresistor. Experiment with several in series.

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steveastrouk (author)2009-07-03

You need a photo-resistor, not a photo-cell - a photoresistor changes resistance with light level. Steve

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Spaceman Spiff (author)2009-07-03

the pot has 3 pins, but only two of them should be being used . This should be pretty simple to replace with a photocell. Just put the two leads of the photocell into the two leads of the pot being used. I hope this helps. I think a photo or diagram would be helpful here.

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