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US3898565A
Expired / Lapsed
US
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Magnetic wave communication system
Assignee: Mishima Kosan Co Ltd
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Filing: 1973-10-18
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Granted: 1975-08-05
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Expires: 1993-10-18
Abstract
Abstract A receiver for a magnetic wave communication system comprising antenna means, a signal treating circuit, an amplifier and a reproducing means. The antenna means includes a casing and an antenna member consisting of a core conductor, a magnetic thin film, and a coil. The signal treating circuit comprises an impedance means and a diode detector. The antenna means receives the transmitted audio frequency magnetic field signal and converts the magnetic field signal to a current corresponding with the audio frequency magnetic field signal.
Inventors
- 👤 Shinjiro Takeuchi
- 👤 Satoshi Ichioka
- 👤 Tadashi Inoue
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:22
CPC Classifications
H; H04; H04B; H04B5/00; H04B5/20; H04B5/24; H04B5/26; H04B5/70; H04B5/73
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
169 words
A receiver for use in a magnetic wave communication system comprising: an antenna means for converting an incoming audio frequency magnetic field to an electric signal having positive and negative asymmetrical amplitudes, said antenna means comprised of an orthogonal type magnetic sensing antenna having an inductor coil to prevent deterioration of sensitivity in the signal and a casing, said antenna being housed in said casing; a conductor having a magnetic thin film coated thereon, said conductor being formed on said inductor coil; an excitation power source connected to said conductor to excite said thin film; a signal treating means coupled to said inductor coil for detecting an amplitude difference between said positive and negative asymmetrical amplitudes of thE electric signal to produce a detected output signal; and a control circuit means coupled to said signal treating means having a resistor and a speaker, and including said resistor operatively coupled between said speaker, and said antenna means whereby said speaker converts said detected output signal to an audible output signal.
Claim 2
Dependent Claim
169 words
A receiver for use in a magnetic wave communication system comprising: an antenna means for converting an incoming audio frequency magnetic field to an electric signal having positive and negative asymmetrical amplitudes, said antenna means comprised of an orthogonal type magnetic sensing antenna having an inductor coil to prevent deterioration of sensitivity in the signal and a casing, said antenna being housed in said casing; a conductor having a magnetic thin film coated thereon, said conductor being formed on said inductor coil; an excitation power source connected to said conductor to excite said thin film; a signal treating means coupled to said inductor coil for detecting an amplitude difference between said positive and negative asymmetrical amplitudes of thE electric signal to produce a detected output signal; and a control circuit means coupled to said signal treating means having a resistor and a speaker, and including said resistor operatively coupled between said speaker, and said antenna means whereby said speaker converts said detected output signal to an audible output signal.
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) | 1978-08-04 | 1979-02-03 | 1979-08-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-04 | 1983-02-03 | 1983-08-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-04 | 1987-02-03 | 1987-08-05 | $7700.00 | Window Closed / Lapsed |