A broadband RF noise generator

A simple broadband noise generator was constructed which produced substantial noise power over the frequency range from 10 mc to 1,000 mc. The measured noise factors were 90 db or better over this range. The noise was generated by an electric arc discharge that operated in a conventional RC relaxation oscillator circuit. A continuous spectrum was produced because of the natural incoherence in the pulse repetition rate of such a circuit. The mechanism of operation is described, along with an experimental tube that was constructed for the purpose of demonstrating the principle.