US3586986A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency discriminator
Assignee: International Standard Electric Corp
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Filing: 1969-02-19
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Granted: 1971-06-22
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Expires: 1989-02-19
Abstract
Abstract A frequency selective network is coupled to an input signal source and two output detecting circuits to produce the desired output signal. The selective network is coupled in parallel with the source and includes a two terminal reactive network exhibiting at least one reversal of sign at a predetermined frequency in series with a two terminal resistive network. One of the detecting circuits includes a unity gain transistor amplifier coupled to be responsive to the voltage across the reactive network, and a first output transistor coupled to the output of the amplifier. The other of the detecting circuits includes a second output transistor coupled to be responsive to the voltage across the resistive network. The first output transistor is of a conductivity type opposite to the conductivity type of the second output transistor and the transistor of the amplifier and the collectors of the first and second output transistors are connected directly together to provide the desired output signal.
Inventors
- 👤 Jean Victor Martens
- 👤 Marcel Clement Rene Natens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:30
CPC Classifications
H; H03; H03D; H03D3/00; H03D3/26
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
120 words
An angle modulation detector comprising: a source of input signals; a frequency selective network coupled to said source including: two-terminal reactive and resistive network exhibiting two reversals of sign at two predetermined frequencies corresponding to opposite peaks in the output signal of said detector at sAid predetermined frequencies; two output detecting circuits coupled to said frequency network to produce said output signal; and an amplifier having a relatively high input impedance; said reactive and resistive networks being connected in series across said source; the input of said amplifier being coupled across said reactive network; one of said detecting circuits being coupled to the output of said amplifier; and the other of said detecting circuits being coupled across said resistive network.
Claim 2
Dependent Claim
120 words
An angle modulation detector comprising: a source of input signals; a frequency selective network coupled to said source including: two-terminal reactive and resistive network exhibiting two reversals of sign at two predetermined frequencies corresponding to opposite peaks in the output signal of said detector at sAid predetermined frequencies; two output detecting circuits coupled to said frequency network to produce said output signal; and an amplifier having a relatively high input impedance; said reactive and resistive networks being connected in series across said source; the input of said amplifier being coupled across said reactive network; one of said detecting circuits being coupled to the output of said amplifier; and the other of said detecting circuits being coupled across said resistive network.
Claim 3
Dependent Claim
129 words
A detector according to claim 1, further including a power supply having two terminals; and wherein said one of said detecting circuits includes a first transistor of one conductivity type; and said other of said detecting circuits includes a second transistor of a conductivity type opposite said one conductivity type; said first and second transistors having their emitter-to-collector circuits coupled in series across the terminals of said power supply with the collector of said first transistor being directly connected to the collector of said second transistor; said output signal being obtained at said collectors of said first and second transistors; the base-to-emitter circuit of said first transistor being coupled across the output of said amplifier; and the base-to-emitter circuit of said second transistor being coupled across said resistive network.
Claim 4
Dependent Claim
41 words
A detector according to claim 2, wherein said amplifier includes a third transistor having a conductivity type the same as the conductivity type of said second transistor; said reactive network being resistively coupled across the base-to-emitter circuit of said third transistor.
Claim 5
Dependent Claim
94 words
A detector according to claim 3, wherein the base of said third transistor is directly connected to one terminal of said reactive network and biased by a first resistor coupled between the base of said third transistor and one terminal of said power supply, the resistance of said first resistor being equal to the collector load resistance of said third transistor; and a second resistor couples the emitter of said third transistor to the other terminal of said reactive network, said second resistor having a resistance equal to the resistance of said first resistor.
Claim 6
Dependent Claim
115 words
A detector according to claim 2, wherein a first resistor is coupled to the base of said first transistor; a second resistor is coupled to the base of said second transistor; a first diode poled in a given direction is coupled between said first resistor and one terminal of said power supply; a second diode poled in a direction opposite said given direction is coupled between said second resistor and the other terminal of said power supply; and a third resistor coupled between the opposite electrodes of said first and second diodes. said output signal is obtained between said collectors of said first and second transistors and one of the terminals of said power supply.
Claim 7
Dependent Claim
25 words
A detector according to claim 2, wherein said source includes an emitter-follower having a third transistor of conductivity type the same as said second transistor.
Claim 8
Dependent Claim
35 words
A detector according to claim 5, wherein the resistance of said resistive network is substantially equal to the impedance of said reactive network at a frequency which is the geometric means of said predetermined frequencies.
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) | 1974-06-21 | 1974-12-21 | 1975-06-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-21 | 1978-12-21 | 1979-06-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-21 | 1982-12-21 | 1983-06-22 | $7700.00 | Window Closed / Lapsed |