Just wondering which resistor I'd replace with a variable resistor, and of what approximate value, to end up between 1 and 15Hz pulse output? I know the frequency of the output for 555 can be derived from a formula involving the two resistor values, but I'm not an electrical engineer and I'm over my head here.
http://www.simple-electronics.com/2010/10/555-timer-calculator-monostable-and.html 555 TIMER ASTABLE OPERATION is the mode you want changing R2 to a 500k Pot should get you between 1-15hz from my experimenting with the calculator and reading best practices from datasheets (i.e. make R2 the variable one, not R1 etc)
