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. 29, 1977
Filed:
Nov. 10, 1976
Dieter Lohrmann, Lanham, MD (US);
The United States of America as represented by the Secretary of the Army, Washington, DC (US);
Abstract
A simultaneously amplitude modulated and frequency/phase modulated harmonic ignal generator incorporated in a multichannel AM-FM radio receiver which will indicate to the operator whether or not the receiver is sensitive and is operative to receive signals within any of a plurality of designated channels. The circuit includes a transistor switch which is periodically driven on and off by means of an input signal having a frequency equal to the channel spacing of the receiver and being further controlled by means of an audio frequency signal which is adapted to further modulate the turn-on point of the transistor switch. The signal appearing at the collector of the transistor is fed through a high pass filter to the receiver input as an AM and FM waveform which contains a harmonic at every channel of the receiver and thereby providing a self testing function for the receiver.