Ooops. I wondered why the first serial print was zero … 
To be honest I was too. But its not what this says … 
According to this:
you should be aiming for a current drain of between 1ma and 5ma (0.001 to 0.005 amps).
Plugging those values into your calculator gives this:
Pete.
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hey guy’s, just an FYI but your voltage divider formula is backwards.
the correct formula is Vr2=Vs*(R2/(R1+R2)), as per Ohms Law