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:
May. 30, 1978
Filed:
Mar. 30, 1977
Applicant:
Inventor:
Josef Birlmeier, Deisenhofen, DT;
Assignee:
Siemens Aktiengesellschaft, Munich, DT;
Primary Examiner:
Int. Cl.
CPC ...
H04L / ; H03K / ;
U.S. Cl.
CPC ...
178-3 ; 307236 ; 328118 ;
Abstract
Apparatus is described for monitoring the state, e.g., with regard to polarity, of signal lines in a telecommunication system. An input circuit, by means of high resistances relative to the line resistance, connects the lines to a differential amplifier having a predetermined threshold of response. A component of the amplifier output is applied to the input so as to have a polarity opposite to that of a bias voltage coupled to the amplifier. A capacitive protective circuit connected between the signal lines provides a time delay thereby protecting against interference pulses.