Patent US3778728A successfully refreshed from Google Patents.
US3778728A
Expired / Lapsed
US
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Phaselocked-fm detector apparatus
Assignee: Edmac Associates Inc
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Filing: 1972-04-11
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Granted: 1973-12-11
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Expires: 1992-04-11
Abstract
Abstract A phaselock loop FM detector for detecting an incoming FM signal includes a voltage controlled oscillator (VCO) which produces an output signal and two control circuits, the first of which includes a varactor and causes the oscillator output signal to be at the center frequency of the incoming signal, and the second control circuit includes a second varactor and causes the oscillator output signal to lock on the modulation of the input signal.
Inventors
- 👤 R Nupp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:23
CPC Classifications
H; H03; H03D; H03D3/00; H03D3/02; H03D3/24; H03D3/241; H03B; H03B5/00; H03B5/08; H03B5/12; H03B5/1203; H03B5/1228; H03B5/1237; H03B5/124; H03B5/1243; H03B5/1296
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
181 words
In a phase lock loop detector apparatus adapted to detect a radio frequency signal having center frequency and modulation information components, the detector apparatus includes a voltage control oscillator having a voltage control tank circuit, a phase detector controlled to the voltage control oscillator and a first amplifier coupled to the phase detector, the improvement comprising: a. a first control circuit connected to the first amplifier and including a first varactor coupled to the tank circuit and adapted to produce a voltage signal representative of the modulation information component to the tank circuit; b. a second control circuit coupled to said first amplifier and including a second amplifier, a low pass filter connected to said second amplifier and adapted to pass the center frequency component; and a second varactor coupled to said low pass filter and responsive to the center frequency component passed by said low pass filter for applying a second voltage signal to the tank circuit representative of the center frequency component whereby the voltage control oscillator produces an output signal which has the center frequency and modulation components.
Claim 2
Dependent Claim
181 words
In a phase lock loop detector apparatus adapted to detect a radio frequency signal having center frequency and modulation information components, the detector apparatus includes a voltage control oscillator having a voltage control tank circuit, a phase detector controlled to the voltage control oscillator and a first amplifier coupled to the phase detector, the improvement comprising: a. a first control circuit connected to the first amplifier and including a first varactor coupled to the tank circuit and adapted to produce a voltage signal representative of the modulation information component to the tank circuit; b. a second control circuit coupled to said first amplifier and including a second amplifier, a low pass filter connected to said second amplifier and adapted to pass the center frequency component; and a second varactor coupled to said low pass filter and responsive to the center frequency component passed by said low pass filter for applying a second voltage signal to the tank circuit representative of the center frequency component whereby the voltage control oscillator produces an output signal which has the center frequency and modulation components.
Claim 3
Dependent Claim
18 words
The invention as set forth in claim 1 wherein said voltage controlled oscillator is of a ''''Hartley'''' configuration.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-10 | 1977-06-11 | 1977-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-10 | 1981-06-11 | 1981-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-10 | 1985-06-11 | 1985-12-11 | $7700.00 | Window Closed / Lapsed |