My math says 20ma * 12 = 240ma per hour for the leds.. add a little for the arduino running at 16mhz. On three AA batteries that should get a few weeks of use right?
Can you measure the actual current draw to check it matches your expectations?
You DO have current limiting resistors of some sort in there, don't you?
yes I do, but I thought the resistors dropped the voltage, not the current.
Regardless I have the correct resistors in line with every led. One resistor per led.
Wouldn't the leds burn out if the current was too high?
I checked the current, and with the dial at 200m it read 108.5.