A re-appraisal of the Goldschmidt generator

The early wireless telegraphy transmitters were based on the generation of trains of high frequency oscillations produced by sparks. In the Goldschmidt alternator, an ingenious combination of a standard machine plus external static components generate a series of currents of increasing frequency in low impedance paths. In this alternator the principle of operation does not depend necessarily on the presence of a large number of poles but rather on the generation of successively higher-frequency currents in the machine stator and rotor windings. The principle of operation is described. The reason why this alternator was re-invented at Imperial College and was given an up-to-date theoretical treatment and practical realisation is also discussed.