The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 04, 1977
Filed:
Aug. 21, 1975
Siemens-Albis Aktiengesellschaft, Zurich, CH;
Abstract
Apparatus is disclosed for feeding ringing currents from a ringing current supply to line circuits, and for controlling ringing currents in such line circuits, in telephone and other telecommunication systems having an exchange equipped with a source of supply voltage and having subscriber circuits equipped with a ringing circuit capacitor. The disclosed invention comprises a combination of a junction for feeding ringing currents to line circuits, a diode connected between the feeding junction and a pole of the source of supply voltage, an electronic switching device having a control electrode and being connected between the ringing current supply and the feeding junction, and equipment connected to the control electrode of the switching device for causing the switching device to switch ringing currents on and off instantly and to discharge the ringing circuit capacitor.