GB147434A - Improvements in wireless telegraph transmitters - Google Patents

Abstract

147,434. Ges. f³r Drahtlose Telegraphie. Oct. 24, 1917, [Convention date]. Wireless telegraphy; electric oscillations, producing. - A tone transmitter comprises a valve oscillation generator with its grid circuit influenced by currents of audible frequency also generated by the valve. In the arrangement shown in Fig. 1, the plate-filament circuit of the valve generator 1 includes the aerial 3, and the grid-filament tuned circuit 4 is coupled to the aerial inductance. The tone frequency is produced by the valve 1 by connecting a circuit 8 tuned to the tone frequency in-the aerial circuit, and coupling it to a coil in the grid circuit. Alternatively, the tone circuit may be connected as a shunt across the plate and filament of the valve 1, and coupled to a coil directly connecting the grid and filament. The tone circuit may be disconnected by a switch such as 11, Fig. 1 (Cancelled), the valve then producing continuous oscillations of constant amplitude. The tone may be varied by the optional connexion of different capacities 9, 10 in the tone circuit. The Specification as open to inspection under Sect. 91 (3) (a) comprises also the arrangement shown in Fig. 1 (Cancelled), in which a buzzer 6 is connected through a transformer 7 across a condenser in the grid circuit, so as to supply the tone frequency to the grid. This subject-matter does not appear in the Specification as accepted. Reference has been directed by the Comptroller to Specification 152,365.