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Electronics => Electronics => Topic started by: airman00 on March 02, 2008, 12:34:35 PM

Title: Phototransistors and Photoresistor
Post by: airman00 on March 02, 2008, 12:34:35 PM

Phototransistors and photoresistors can both detect light , correct? Meaning can I substitute a phototransistor for a photoresistor to detect the light from a flashlight?
Thanks,
Eric

Title: Re: Phototransistors and Photoresistor
Post by: ed1380 on March 02, 2008, 02:20:08 PM

http://www.techimo.com/forum/showthread.php?t=32866

first link in google. you can make a phototransistor from a photoresistor and a regular transistor. both very close to being the same.

a photoresistor changes resistance so you'd need to compare it with something to see if it senses light. a phototransistors output is based on the light. also need a compare. just use what you have laying around or what cheaper  ;D

Title: Re: Phototransistors and Photoresistor
Post by: airman00 on March 02, 2008, 02:24:43 PM

thanks ed

i'll play around with them now