Observations on Radio-Frequency Oscillations in Low-Pressure Electrical Discharges

The generation of high-frequency energy by electrical discharges in air at low pressures has been investigated by observations with several types of discharge tube, at frequencies near 200 Mc/s and below 2 Mc/s. Random noise of high intensity was observed in both these frequency ranges, and was found to be associated with a field reversal in the discharge Coherent oscillations were also observed at the lower frequencies, and there was evidence that these were the cause of the striations of the positive column