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:
Jun. 28, 1977
Filed:
Sep. 02, 1976
Robert R Podowski, Elmhurst, IL (US);
Zenith Radio Corporation, Glenview, IL (US);
Abstract
A battery powered portable acoustic transmitter comprises a plurality of single-pole, momentary contact switches, a type 555 pulse producing integrated circuit chip, and an electroacoustic transducer and matching tuning coil. An RC timing circuit includes a plurality of resistors selectively connectable in the timing circuit by the switches to vary the pulse output frequency. A transistor output circuit amplifies the pulses for driving the transducer. A plurality of diodes supply power to the chip and the transistor output circuit whenever a switch is activated. The integrated circuit chip, resistors, diodes and transistor are part of an active thick film circuit.