Rca1948FrequencyModu.. - The New Jersey Antique Radio Club

32 FREQUENCY MODULATION, Volume 1intervals of lower instantaneous peak value reduces the energy contentof the noise in the output; hence some idea of the magnitude of thiseffect can be obtained from the root-mean-square characteristics of thenoise.The curves of Fig. 10 are similar to those of Fig. 9 except that theroot-mean-square signal-noise ratios are plotted as ordinates. Since thecrest factor of the signal is three decibels and that of fluctuation noiseisabout thirteen decibels (as later curves will show), the root-meansquaresignal-noise ratios are ten decibels higher than the correspondingpeak ratios. It can be seen that the root-mean-square characteris-