5V to 3V Resistor Change.

Using Arduino General Electronics
#1

Hi, To All That Read This.

What I would like some help on is. I came across this (Arduino EMF Detector).
Here is the link http://duino4projects.com/arduino-emf-detector/

It works great, but I would like to use A Moteino. Moteino is Arduino clone.
But the Moteino is running at 3.3 volts.

The Arduino is running at 5 volts. The resistor used on the project is (3.3M).
What I need to know is if, I am doing the Ohm’s Law Calculator, right?

Arduino EMF Detector

 Voltage (E) = Current (I) * Resistance (R)
Power (watts) = Voltage (E) * Current (I)

Voltage (E): 5	
Current (I): 0 			
Resistance (R): 3.3m      Megaohms
Power (P): .000001

Moteino

 Voltage (E) = Current (I) * Resistance (R)
Power (watts) = Voltage (E) * Current (I)

Voltage (E): 5	
Current (I): 0 			
Resistance (R): .9m	 Megaohms	
Power (P): .000001

So at 3 volts, the resistor I need to use is (White Black Yellow Gold) = .9 Megaohm or 900K

#2

Your over thinking this circuit. The 3.3m is high imedance and not really critical. Anyhthing above 1M should be fine, but 2-3M would be okay as well.

#3