US3582799A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Discriminator circuit of the charge transfer type
Assignee: General Dynamics Corp
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Filing: 1969-08-25
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Granted: 1971-06-01
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Expires: 1989-08-25
Abstract
Abstract An FM signal discriminator circuit is described having a pair of emitter follower transistors of complementary symmetry cross coupled to each other. The output is taken at a base to emitter junction of one of the transistors so that voltage drops across the base to emitter junctions cancel, thereby enhancing linearity and temperature stability of the circuit. Discriminating action is obtained by transfer of charge between capacitors, one of which is contained in a charging circuit connected between the cross coupled transistors. The voltage across the last-mentioned capacitor is a function of the frequency of an input signal.
Inventors
- 👤 Terence Patrick Reid
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:38
CPC Classifications
H; H03; H03D; H03D3/00; H03D3/02; H03D3/04; H03D3/06; H03D3/14
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
200 words
A discriminator circuit which comprises a. a first And a second active circuit element, each having input, output and control terminals, b. said second element being connected as an input follower and having an output resistor connected to its input terminal across which output resistor the output voltage of said discriminator circuit is obtainable, c. means for interconnecting said first and second elements in cross coupled relationship with said control terminal of said first element connected to said second element input terminal and said first element input terminal connected to said second element control terminal, d. said connection between said first element input terminal and said second element control terminal including a first resistor connected in series therebetween, a first capacitor connected between the junction of said first resistor and second element control terminal and a point of reference potential, and a second resistor connected between said last-named junction and said reference potential point, and e. input signal operated means including a second capacitor connected to said first element input terminal for applying voltages to the circuit elements in said connection between said first element input terminal and said second element control terminal as a function of said input signal.
Claim 2
Dependent Claim
200 words
A discriminator circuit which comprises a. a first And a second active circuit element, each having input, output and control terminals, b. said second element being connected as an input follower and having an output resistor connected to its input terminal across which output resistor the output voltage of said discriminator circuit is obtainable, c. means for interconnecting said first and second elements in cross coupled relationship with said control terminal of said first element connected to said second element input terminal and said first element input terminal connected to said second element control terminal, d. said connection between said first element input terminal and said second element control terminal including a first resistor connected in series therebetween, a first capacitor connected between the junction of said first resistor and second element control terminal and a point of reference potential, and a second resistor connected between said last-named junction and said reference potential point, and e. input signal operated means including a second capacitor connected to said first element input terminal for applying voltages to the circuit elements in said connection between said first element input terminal and said second element control terminal as a function of said input signal.
Claim 3
Dependent Claim
23 words
The invention as set forth in claim 1 wherein said second resistor has a value of resistance much greater than said first resistor.
Claim 4
Dependent Claim
39 words
The invention as set forth in claim 2 wherein the time constant of a circuit including said second capacitor and said first element input to output terminal path is much less than half the period of said input signal.
Claim 5
Dependent Claim
37 words
The invention as set forth in claim 3 wherein the time constant of the circuit including said first and second capacitors and said first and second resistors is much more than the period of said input signal.
Claim 6
Dependent Claim
31 words
The invention as set forth in claim 4 including an input signal source which is a square wave having a potential equal to said reference potential during alternate half cycles thereof.
Claim 7
Dependent Claim
42 words
The invention as set forth in claim 5 wherein said first and second elements are first and second transistors having base electrodes which provide said control terminals, emitter electrodes which provide said input terminals and collector electrodes which provide said output terminals.
Claim 8
Dependent Claim
18 words
The invention as set forth in claim 6 wherein said first and second transistors are of complementary types.
Claim 9
Dependent Claim
24 words
The invention as set forth in claim 7 wherein said first transistor is of PNP type and said second transistor is of NPN type.
Claim 10
Dependent Claim
37 words
The invention as set forth in claim 8 wherein said collector electrodes of said first and second transistors are respectively connected to source of operating voltage which are negative and positive with respect to said reference potential.
References Cited (Backward Citations)
US3188495A
Cited
US3506848A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-31 | 1974-11-30 | 1975-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-31 | 1978-11-30 | 1979-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-31 | 1982-11-30 | 1983-06-01 | $7700.00 | Window Closed / Lapsed |