Rca1948FrequencyModu.. - The New Jersey Antique Radio Club

1224 FREQUENCY MODULATION, Volume IThe curves of Figures 7 and 8 for fluctuation noise assume athermionic agitation and tube-hiss noise level equivalent to one peakmicrovolt per meter (0.224 r-m-s microvolts per meter). This correspondsto an r-m-s noise voltage of 0.52 microvolts in series with adummy antenna at the input terminals of the amplitude-modulationreceiver. Such a noise voltage is about that which would be obtainedwith good design using an 1852 radio-frequency amplifier tube. Allof the ratios for these curves were converted from peak to r-m-s ratiosto correspond to the general practice in considering this type of noise.This was done by adding 10 decibels to the ratios. The figure of 10"