This app will determine the S/N for FM voice when the user enters the baseband maximum frequency and the RF channel bandwidth in kHz, the de-emphasis in dB and the receiver C/N ratio in dB. Carson's rule is used to determine the peak frequency deviation.

As an example, enter baseband maximum frequency (BBF BW) = 3.4, RF channel bandwidth (RF BW) = 45, C/N = 13 and the de-empasis P = 7, hit "Calculate" and your result should be 48.0 dB.