The duty cycle associated with forward-scattered echoes from meteor trails

Signals propagated by meteor trails from a transmitter at Stanford, California have been monitored in San Diego. The duty cycle, percent of time that received signal exceeds a given threshold level, is analyzed in terms of its variation with threshold level at a fixed time and its variation during the day at a fixed threshold level. The duty cycle varies with threshold level A approximately as 1/A^{m}. This variation is similar to the distribution of peak amplitudes of the signal bursts. Overdense trails account for most of the duty cycle and the diurnal variation of the duty cycle follows the diurnal variation of the rates of occurrence of signal bursts except for an enhancement in duty cycle around noon.