Patent US4500920A successfully refreshed from Google Patents.
US4500920A
Expired / Lapsed
US
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RF Modulator
Assignee: Alps Alpine Co Ltd
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Filing: 1982-07-01
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Granted: 1985-02-19
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Expires: 2002-07-01
Abstract
Abstract In furnishing an RF modulator with a reference signal generator for generating a specified test signal, and a switching circuit for switching a video signal and the test signal on occasion; the reference signal generator and the switching circuit are received in a shield case of the RF modulator, thereby to prevent radiated interferences.
Inventors
- 👤 Tohru Ohyama
- 👤 Shigeru Nigorikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 19:04
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/38; H04N5/40; H04N17/00; H04N17/06; H05; H05K; H05K9/00; H05K9/0064
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
71 words
In an RF modulator having a modulation circuit which modulates a video signal of a video tape recorder or the like and converts it into a TV signal; an RF modulator device characterized in that a reference signal generator which generates a specified test signal to be switched from said video signal and supplied to said modulation circuit on occasion is received in a shield case which receives said RF modulator.
Claim 2
Dependent Claim
71 words
In an RF modulator having a modulation circuit which modulates a video signal of a video tape recorder or the like and converts it into a TV signal; an RF modulator device characterized in that a reference signal generator which generates a specified test signal to be switched from said video signal and supplied to said modulation circuit on occasion is received in a shield case which receives said RF modulator.
Claim 3
Dependent Claim
78 words
In an RF modulator having a modulation circuit which modulates a video signal of a video tape recorder or the like and converts it into a TV signal; an RF modulator device characterized in that a reference signal generator which generates a specified test signal, and a switching circuit which supplies said video signal and said test signal to said modulation circuit by switching them on occasion, are received in a shield case which receives said RF modulator.
Claim 4
Dependent Claim
78 words
In an RF modulator having a modulation circuit which modulates a video signal of a video tape recorder or the like and converts it into a TV signal; an RF modulator device characterized in that a reference signal generator which generates a specified test signal, and a switching circuit which supplies said video signal and said test signal to said modulation circuit by switching them on occasion, are received in a shield case which receives said RF modulator.
Claim 5
Dependent Claim
77 words
In a RF modulator having means including a modulation circuit for modulating a video signal from a video recorder or the like and converting it into a signal for a video monitor, and means including a reference signal generator and a switching circuit for producing a test signal to be delivered on occasion to said monitor, the improvement wherein said modulation circuit, said reference signal generator and said switching circuit are housed in a common shield case.
Claim 6
Dependent Claim
77 words
In a RF modulator having means including a modulation circuit for modulating a video signal from a video recorder or the like and converting it into a signal for a video monitor, and means including a reference signal generator and a switching circuit for producing a test signal to be delivered on occasion to said monitor, the improvement wherein said modulation circuit, said reference signal generator and said switching circuit are housed in a common shield case.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-19 | 1988-08-20 | 1989-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-19 | 1992-08-20 | 1993-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-19 | 1996-08-20 | 1997-02-19 | $7700.00 | Window Closed / Lapsed |