US3576495A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tuning circuit having means for compensating for the coupling of the local oscillator signal to the antenna winding
Assignee: Alps Alpine Co Ltd
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Filing: 1969-01-10
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Granted: 1971-04-27
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Expires: 1989-01-10
Abstract
Abstract 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
- 👤 Akiyuki Yoshizato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:34
CPC Classifications
H; H03; H03D; H03D9/00; H03D9/06; H03D9/0608; H03D9/0625
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
106 words
A tuner for use in a communications receiver comprising an antenna winding, first signal-carrying means in inductive coupling relation with said antenna winding, second signalcarrying means inductively coupled to said first means, means for producing a first signal in said second means, there being a tendency to generate an unwanted signal in said antenna winding corresponding to said first signal, and additional means operatively inductively coupling said second means and said antenna winding and effective to induce in said antenna winding a second signal in opposing phase relation to said unwanted signal and effective to reduce or substantially cancel said unwanted signal in said antenna winding.
Claim 2
Dependent Claim
106 words
A tuner for use in a communications receiver comprising an antenna winding, first signal-carrying means in inductive coupling relation with said antenna winding, second signalcarrying means inductively coupled to said first means, means for producing a first signal in said second means, there being a tendency to generate an unwanted signal in said antenna winding corresponding to said first signal, and additional means operatively inductively coupling said second means and said antenna winding and effective to induce in said antenna winding a second signal in opposing phase relation to said unwanted signal and effective to reduce or substantially cancel said unwanted signal in said antenna winding.
Claim 3
Dependent Claim
32 words
The tuner of claim 1, in which said coupling means comprises a winding section in operative series connection with said antenna winding and arranged in loose inductive relationship with said second means.
Claim 4
Dependent Claim
34 words
The tuner of claim 1, in which said coupling means comprises a winding section in operative parallel circuit relationship with said antenna winding and arranged in loose inductance coupling relationship with said second means.
Claim 5
Dependent Claim
16 words
The tuner of claim 3, comprising impedance matching means in series connection with said winding section.
Claim 6
Dependent Claim
34 words
The tuner of claim 1, in which said coupling means comprises a conducting line connected at one end to said antenna winding and having its other end loosely inductively coupled to said second means.
Claim 7
Dependent Claim
23 words
The tuner of claim 1, in which said coupling means comprises capacitance means operatively connected between said antenna winding and said second means.
Claim 8
Dependent Claim
45 words
The tuner of claim 1, in which said antenna winding comprises first and second winding section, said first winding section being closely inductively coupled to said first means said second winding section being loosely inductively coupled to said inductance means and defining said coupling means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-26 | 1974-10-26 | 1975-04-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-26 | 1978-10-26 | 1979-04-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-26 | 1982-10-26 | 1983-04-27 | $7700.00 | Window Closed / Lapsed |