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:
Aug. 18, 1992

Filed:

Jun. 13, 1990
Applicant:
Inventor:

Tadashi Kosuga, Saitama, JP;

Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04B / ;
U.S. Cl.
CPC ...
455318 ; 455319 ; 455326 ;
Abstract

An RF tank circuit includes a coil with a center tap, the RF tank circuit being for receving an input RF signal, and for providing a balanced mixer circuit by being arranged in one of: a) receiving a local signal through second and third capacitors at first and second coil ends, respectively, with the center tap grounded; and, b) receiving a local signal at the center tap. An impedance is connected between the first and second coil ends of the RF tank circuit, the impedance providing low impendance for a predetermined intermediate frequency signal, and high impedance for a predetermined high frequency signal and a local signal. A bias resistor is connected between a middle connecting point of the impedance and ground. The coil of the RF tank cicuit can be one of a primary and second winding of an isolation transformer, with a remaining one of the primary and secondary windings being connected to an RF signal source, the isolation transformer being for preventing a leakage of a local signal to the RF signal source.


Find Patent Forward Citations

Loading…