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. 03, 1984
Filed:
Nov. 27, 1981
Applicant:
Inventors:
James A Murray, Sawbridgeworth, GB;
David Nyman, New Barnet, GB;
Assignee:
International Standard Electric Corporation, New York, NY (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H04B / ; H03H / ;
U.S. Cl.
CPC ...
333 18 ; 179 / ; 1791 / ; 330254 ; 330282 ;
Abstract
An adaptive equalizer for a twisted pair telephone line comprises a differential input/output amplifier, with the line connected to its positive input via a resistor and DC blocking capacitors. The junction of these capacitors is grounded via an adjustable impedance. The amplifier has a feedback loop with another adjustable impedance also connected to the negative input of the amplifier. Line impedance variations vary the impedance of both of the adjustable impedances, which, include diodes to separately compensate for the line's attenuation and frequency characteristics.