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:
Nov. 30, 1982
Filed:
Apr. 09, 1980
Kenzo Tanabe, Katano, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A superheterodyne type multiplex signal receiver for multiplex signal transmission systems for receiving two independent signals transmitted by amplitude modulation and angle modulation of single carriers, and for detecting an intermediate frequency by an intermediate frequency detector when changing the local oscillating frequency by a dial operation to select the received signal. The receiver has a switching circuit so composed that it operates a demodulation circuit which demodulates, from the modulated carrier, the two independent signals, which are then transmitted to two independent audio amplifiers provided at a later stage of an intermediate frequency amplifier for driving two speakers for reception of the multiplex signal, when the intermediate frequency is extremely close to a normally determined frequency. The switching circuit also transmits to the two independent audio amplifiers the demodulated signals obtained from an envelope detection circuit when the intermediate frequency is remote from the normally determined frequency.