GB189693A - Improvements in wireless telegraph receivers - Google Patents

Abstract

189,693. Turner, L. S. Feb. 8, 1922. Multiplex signalling; thermionic amplifiers; atmospherics, limiting.-A single antenna A is connected to a plurality of differently-tuned receiving circuits #<1>, #<2>, #<3> through an equal number of triodes T<1>, T<2>, T<3>, each of the circuits being adjustable without affecting the currents in the antenna. The grids of the triodes are connected across the antenna, as shown. The oscillatory plate circuits #<1>, #<2>, #<3> have preferably no mutual coupling, but are linked to separate detector circuits for receiving simultaneously a number of signals on different wave-lengths. They may be variously distuned from the desired signal in order to lessen the effect of atmospherics. The aerial should be of large effective height, and may be suitably aperiodic; or it may be more or less tuned to one or other of the wavelengths concerned, or to some intermediate wave-length. The electrostatic reaction between the. grids and plates of the triodes may be balanced out by the method described in Specification 189,645.