Observations on the DE 1 spacecraft of ELF/VLF waves generated by an ionospheric heater

DE 1 satellite radio observations were conducted in the 1525-5925 Hz range during a pass over an ionospheric heating facility; the waves were detected during a 2-min period, and the measurements indicated pulse-stretching by a few hundred msec, in conjunction with spectral broadening of about 10 Hz. The observed signal delays and pulse distortion are not consistent with expectations assuming propagation in a smooth magnetosphere between the assumed 'polar electrojet antenna' in the ionospheric D/E region and the 11,000-km altitude of the satellite. Scattering by density irregularities is judged the likely sources of the spectral broadening and delays.