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.

Date of Patent:
Jun. 16, 1987

Filed:

Sep. 18, 1985
Applicant:
Inventors:

Masami Miura, Tokyo, JP;

Naotoshi Higashiyama, Tokyo, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04H / ;
U.S. Cl.
CPC ...
381 10 ; 381 11 ; 381 13 ;
Abstract

A circuit is provided for detecting the level of noises in received FM signals in an AM/FM receiver which includes at least an FM intermediate-frequency amplifier, an FM detector connected thereto, an AM intermediate-frequency amplifier and an AM detector connected thereto. This FM noise level detecting circuit includes a frequency converter receiving the output of the FM detector for converting noise components contained in the output of the FM detector into a noise signal of the AM intermediate-frequency, which is in turn outputted to the AM intermediate-frequency amplifier, so that the converted noise signal is amplified by the AM intermediate-frequency amplifier and then detected by the AM detector to produce a DC signal. The signal thus obtained is not only representative of the level of the noise contained in the received FM signal, but also representative of the received FM signal strength.


Find Patent Forward Citations

Loading…