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:
Feb. 17, 1987
Filed:
Jun. 18, 1985
Applicant:
Inventor:
Edward J Whittaker, Bishops Stortford, GB;
Assignee:
International Standard Electric Corporation, New York, NY (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04M / ;
U.S. Cl.
CPC ...
379388 ; 379387 ;
Abstract
In a loudspeaking telephone the power supply to the loudspeaker amplifier is shunted by a regulator which functions as a programmable Zener diode. Under conditions of low available line current, e.g. where two similar instruments are operated in parallel at the end of a long line, the regulator voltage is reduced in value to disable the amplifier and conserve power to maintain the basic operating functions of the telephone.