http://trace.wisc.edu/docs/2004-About-dB/Passing bus or truck at 10 ft. or food blender at 3 ft. 90
it works now..but who knos if the numbers i hit are proper...aslo the K factore WAS NOT on the side of the sensor...but i leaft it at 178 ...The k factor number you need to put in is on your sensor.
Also, you may get erractic readings because of ac ripple in your electrical lines. Are you running any big power items off the same outlet or in the same room? Battery chargers, a/c units, etc.