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. 03, 1987
Filed:
Jun. 21, 1985
Applicant:
Inventor:
Edward J Whittaker, Bishops Stortford, GB;
Assignee:
International Standard Electric Corporation, New York, NY (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H04M / ;
U.S. Cl.
CPC ...
379383 ; 379361 ;
Abstract
A transmission chip for a telephone subscriber's instrument can be used in a variety of modes, some of which involve use with other chips. Depending on which mode is in force, different amplifiers are used. Thus for plain ordinary telephone (POT) service, amplifiers 30,35 and 43 are used, for loudspeaking mode amplifiers 30, 35 and 43 are used, for handsfree use amplifiers 35, 43 and 46 are used, while for VF 'dialling' amplifier 46 is used. To save power, the control block (42) detects the mode in which the set is operating and, via a control bus, operates electronic switches to disable the amplifiers not needed.