The Planted Tank Forum - View Single Post - DIY PAR meter, Yeah you heard me
View Single Post
post #38 of (permalink) Old 11-11-2010, 04:15 PM Thread Starter
Children Boogie
mistergreen's Avatar
Join Date: Dec 2006
Location: Cincinnati
Posts: 16,743
Originally Posted by keithy View Post
what data does the ardiuno gave you as an output and how do you translate that to PAR reading? I am new to electronics but would like to learn and prehaps provide some input to help out.
All photodiode will output a small voltage when excited by light but the voltage alone is not not good enough in terms of resolution.
So what you do is apply 5Volts through it and gather the output signal from the diode (0V-5V).
Here's a typical setup (photoresistor/photodiode)

Originally Posted by keithy View Post
the $3 photodiode data you provided does looks better and somewhat matches the $17 photodiode. good find.

I am very interested to find out how everything turns out. I have been reading this thread every day since it started. With Hoppy providing useful input, I have a strong feeling it will turn out good.
Yeah, I think it'll turn out well. I'll go ahead and get the hamamatsu diodes. I think I'll get 5 diodes for that $17. I can sell off the rest to you guys.

mistergreen is offline  
For the best viewing experience please update your browser to Google Chrome