Improvements relating to electrical circuits

Abstract

Abstract 369,304. Multiplex telegraphy and telephony ; thermionic distributors. KOLSTER-BRANDES, Ltd., Cray Works, Sidcup, Kent.-(Kolster Radio Corporation; 200, Mt. Pleasant Avenue, Newark, New Jersey, U.S.A.) Jan. 3, 1931, No. 290. [Classes 40 (iii) and 40 (v).] A plurality of signal or control circuits 16 .. 19 are activated in turn from a single A.C. source 11 by coupling to the source at 12 a pair of circuits in one of which the current is given a leading phase by means of the condenser C, and in the other a lagging phase bymeans of the inductance L. The two circuits each include a pair of transformer primary coils, and the secondary coils are star connected at 9 and are each connected to the grid of a valve 1 .. 4. The valves are thus activated in turn and energize the signal or control circuits 16 .. 19 which are coupled to their plate circuits. In a modification, Fig. 4 (not shown), the starconnected secondaries are connected to electromagnetic relays which close their contacts in turn in the signal or control circuits. Multiplex telephony or telegraphy may be effected by inserting signalling instruments in each controlled circuit, the several circuits being joined together to form a single transmission line.

Inventors

No inventors recorded.

Bibliographic Details