GB359761A - Improvements in or relating to power supply circuits suitable for use in connection with radio and like receivers - Google Patents

Abstract

359,761. Converting pulsating currents into steady continuous currents. MARCONI'S WIRELESS TELEGRAPH CO., Ltd., Marconi House, Strand, London. -(Assignees of Roberts, W. van B. ; 155, Hodge Road, Princeton, New Jersey, U.S.A.) Nov. 20, 1930, No. 34993. Convention date, Nov. 20. [Class 38 (ii).] In an arrangement for converting pulsating current into steady continuous current for supply to wireless receivers for example, current from a rectifier 31 is partially smoothed by being passed through a filter comprising a series choke 34 and shunt condensers 35, 26, and the remaining pulsations are removed from the output circuit by connecting in series with the output potential divider 37 a valve 39 the impedance of which is caused to vary with the pulsations so as to maintain a constant current through the potential divider. The variation of impedance is effected by a grid energized by a transformer 41 through which the pulsating current flows, a condenser 40 being connected in series with the primary to eliminate the unidirectional component. Cathode heating current for the valve 39 may be obtained either from a separate secondary winding on the supply transformer 30 or from the potential divider 37. In the latter case, a switch 46 is provided to shortcircuit the anode-cathode path of the valve during starting. Such a switch may also be provided when the cathode is otherwise heated in order that partially smoothed output current may be made available if the valve becomes burnt out.