US3665470A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mistlined vor receiver alarm
Assignee: Collins Radio Co
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Filing: 1970-08-07
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Granted: 1972-05-23
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Expires: 1990-08-07
Abstract
Abstract This invention relates to methods and apparatus for monitoring a frequency outside the standard VOR modulation spectrum to prevent reception of false information when a VOR receiver has been mistuned 50 kHz from the transmitting frequency of a desired ground station, and there is no actual ground station transmitting on the wrongly selected frequency.
Inventors
- 👤 William R Hemme
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:43
CPC Classifications
G; G01; G01S; G01S1/00; G01S1/02
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
56 words
The method of detecting adjacent-channel mistuning of a VOR receiver; said method comprising the steps of: monitoring a predetermined harmonic of a frequency transmitted by a VOR ground station; and activating an alarm when the magnitude of said predetermined harmonic exceeds a preselected threshold value above the magnitude of said predetermined harmonic under correct tuning conditions.
Claim 2
Independent Claim
56 words
The method of detecting adjacent-channel mistuning of a VOR receiver; said method comprising the steps of: monitoring a predetermined harmonic of a frequency transmitted by a VOR ground station; and activating an alarm when the magnitude of said predetermined harmonic exceeds a preselected threshold value above the magnitude of said predetermined harmonic under correct tuning conditions.
Claim 3
Dependent Claim
23 words
The method of claim 1 wherein: said predetermined harmonic is a harmonic of the 9,960 Hz subcarrier transmitted by a VOR ground station.
Claim 4
Dependent Claim
24 words
The method of claim 1 wherein: said predetermined harmonic is the second harmonic of the 9,960 Hz subcarrier transmitted by a VOR ground station.
Claim 5
Dependent Claim
12 words
The method of claim 1 wherein: said predetermined harmonic is 19,920 Hz.
Claim 6
Dependent Claim
57 words
Apparatus for detecting adjacent-channel mistuning of a VOR receiver; said apparatus comprising: monitor means monitoring a predetermined harmonic of a frequency transmitted by a VOR ground station, and alarm means connected to receive signals from said monitor means and responsive to values of said predetermined harmonic exceeding a preselected threshold value to indicate that mistuning has ccurred.
Claim 7
Dependent Claim
57 words
Apparatus for detecting adjacent-channel mistuning of a VOR receiver; said apparatus comprising: monitor means monitoring a predetermined harmonic of a frequency transmitted by a VOR ground station, and alarm means connected to receive signals from said monitor means and responsive to values of said predetermined harmonic exceeding a preselected threshold value to indicate that mistuning has ccurred.
Claim 8
Dependent Claim
19 words
The apparatus of claim 5 wherein: said monitor means comprises a bandpass filter passing substantially only said predetermined harmonic.
Claim 9
Dependent Claim
28 words
The apparatus of claim 5 wherein: said monitor means comprises filter means passing substantially only a harmonic of the 9,960 Hz subcarrier transmitted by a VOR ground station.
Claim 10
Dependent Claim
19 words
The apparatus of claim 5 wherein: said monitor means comprises filter means passing substantially only signals at 19,920 Hz.
Claim 11
Independent Claim
58 words
The method of detecting mistuning of a VOR receiver; said method comprising the steps of: monitoring a predetermined frequency outside the standard VOR modulation spectrum transmitted by a VOR ground station; and activating an alarm when the magnitude of said predetermined frequency exceeds a preselected threshold value above the magnitude of said predetermined frequency under correct tuning conditions.
Claim 12
Independent Claim
58 words
The method of detecting mistuning of a VOR receiver; said method comprising the steps of: monitoring a predetermined frequency outside the standard VOR modulation spectrum transmitted by a VOR ground station; and activating an alarm when the magnitude of said predetermined frequency exceeds a preselected threshold value above the magnitude of said predetermined frequency under correct tuning conditions.
References Cited (Backward Citations)
US3142062A
Cited
US3396395A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-23 | 1975-11-22 | 1976-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-23 | 1979-11-22 | 1980-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-23 | 1983-11-22 | 1984-05-23 | $7700.00 | Window Closed / Lapsed |