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:
Sep. 07, 1982
Filed:
Aug. 27, 1980
Applicant:
Inventors:
Susumu Ushida, Soma, JP;
Hiroyuki Yanagida, Soma, JP;
Assignee:
Alps Electric Co., Ltd., Tokyo, JP;
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03F / ; H04N / ;
U.S. Cl.
CPC ...
330306 ; 358196 ; 330166 ;
Abstract
A buffer amplifier circuit of a wideband tuner has an output transistor. The output terminal of this transistor is grounded through a matching transformer having two taps. One of the taps constitutes a terminal through which the output signal is delivered to a mixer circuit, while the other tap is grounded through a capacitor which constitutes, in cooperation with the matching transformer, a trap circuit. This trap circuit is adapted to trap a frequency which is about twice as high as the low region oscillation frequency of a local oscillator which produces an input to the buffer amplifier circuit.