( 2203 of 2203 ) |
United States Patent | 3,576,495 |
Yoshizato | April 27, 1971 |
A tuning circuit comprises an antenna winding inductively coupled to a first inductor, which in turn is inductively coupled to a second inductor. A local oscillator circuit induces a signal in said second inductor, which signal tends to cause an unwanted signal to be induced in the first inductor and ultimately in the antenna winding. Means are provided to operatively couple the second inductor and the antenna winding to induce in the latter a second signal in opposite phase to the unwanted signal, thereby to substantially cancel the unwanted signal in the antenna winding.
Inventors: | Yoshizato; Akiyuki (Tokyo, JA) |
Assignee: |
Alps Electric Company, Limited
(Tokyo,
JA)
|
Appl. No.: | 04/790,324 |
Filed: | January 10, 1969 |
Mar 27, 1968 [JA] | 19397/68 | |||
Current U.S. Class: | 455/193.1 ; 455/281; 455/292; 455/317; 455/338 |
Current International Class: | H03D 9/06 (20060101); H03H 2/00 (20060101); H03D 9/00 (20060101); H04b 001/26 () |
Field of Search: | 325/430,436,437,438,439,473,475,476,479 |
2823305 | February 1950 | Aschermann |
3042869 | July 1962 | Gosslau |
3130370 | April 1964 | Kondo et al. |