The optimum damping in the auditive reception of wireless telegraph signals

This paper is an account of an experimental investigation of the extent to which it is advantageous to reduce the damping in a receiver for telegraphic signals from modern continuous-wave stations, when the usual rectifier and telephone are used as indicator. It was found possible to produce, hold stable, and measure decrements below those giving optimum reception. Numerous determinations of optimum damping were made, the observed signals coming from six commercial transmitting stations of wave-lengths ranging from about 4 000 to 23 000 m. The several observations on any one station show remarkable accord amongst themselves, and the measured optimum damping exponents for all stations and wave-lengths are found to lie within a narrow range. The significances of speed of signalling in relay and in auditive reception are contrasted.