Mystery solved. I'm not sure if this is an error in your example code or not. In the Imports class you have a line as follows: Public inputRanges() As Integer = New Integer(12) {10, 20, 50, 100, 200, 500, 1000, 2000, 5000, 10000, 20000, 50000, 100000} ' ranges in mV That array contains voltage range...