The reduction of local radio interference caused by h.f. ionospheric sounding equipment

Ionospheric measurements commonly involve the use of high-power pulse-modulated transmissions in the h.f. spectrum and can cause severe interference in nearby receivers. The use of short bursts of pulses instead of continuous transmissions has virtually eliminated interference caused during absorption measurements and the use of horizontal, terminated, folded dipoles with other precautions has minimized interference during vertical incidence soundings.