US3842324A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Induction-keyed control circuit with keying network having variable resonant frequency
Assignee: WAGER ELECTRIC CORP
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Filing: 1972-10-27
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Granted: 1974-10-15
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Expires: 1992-10-27
Abstract
Abstract A control circuit including an oscillator is actuated by a passive keying network which, when inductively coupled to the oscillator tank circuit, will effect amplitude modulation of the normally-constant oscillator output. The keying network comprises a tuned circuit in which the net capacitance is variable by means of a semiconductor diode having a sharply variable junction capacitance. The resonant frequency of the tuned circuit is continuously varied when inductively coupled to the oscillator tank circuit, thereby continuously altering the keying network''s ability to absorb electromagnetic energy from the tank circuit in the oscillator of the control circuit.
Inventors
- 👤 C Atkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:57
CPC Classifications
G; G07; G07C; G07C9/00; G07C9/00174; G07C9/00658; G07C9/00714; G07C9/20; G07C9/28; H; H03; H03K; H03K17/00; H03K17/94; H03K17/945; H03K17/95; H03K17/952; H03K17/9537; H03K17/9542; H03K17/9547
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
81 words
An induction-keyed control circuit comprising: 1. passive keying network means including a tuned circuit having a current- and voltage-controlled variable capacitance, and operative to vary the resonant frequency of said tuned circuit between upper and lower limits when coupled to 2. keyable circuit means normally operative when connected to a source of direct-current power to generate a first, constant output signal and operative in response to the coupling of said keying network means thereto to generate a second, modulated output signal.
Claim 2
Dependent Claim
81 words
An induction-keyed control circuit comprising: 1. passive keying network means including a tuned circuit having a current- and voltage-controlled variable capacitance, and operative to vary the resonant frequency of said tuned circuit between upper and lower limits when coupled to 2. keyable circuit means normally operative when connected to a source of direct-current power to generate a first, constant output signal and operative in response to the coupling of said keying network means thereto to generate a second, modulated output signal.
Claim 3
Dependent Claim
40 words
keyable circuit means normally operative when connected to a source of direct-current power to generate a first, constant output signal and operative in response to the coupling of said keying network means thereto to generate a second, modulated output signal.
Claim 4
Dependent Claim
40 words
keyable circuit means normally operative when connected to a source of direct-current power to generate a first, constant output signal and operative in response to the coupling of said keying network means thereto to generate a second, modulated output signal.
Claim 5
Dependent Claim
14 words
The control circuit according to claim 1 wherein said passive keying network means comprises:
Claim 6
Dependent Claim
20 words
a semiconductor diode having a delayed recovery time, comprising said current- and voltage-controlled variable capacitance in said tuned circuit; and
Claim 7
Dependent Claim
20 words
a semiconductor diode having a delayed recovery time, comprising said current- and voltage-controlled variable capacitance in said tuned circuit; and
Claim 8
Dependent Claim
15 words
a resistance connected in parallel with said first, fixed capacitance to form a discharge path.
Claim 9
Dependent Claim
15 words
a resistance connected in parallel with said first, fixed capacitance to form a discharge path.
Claim 10
Dependent Claim
23 words
a second transistor amplifier driven by the output of said first transistor amplifier to provide an in-phase feedback signal to said tank circuit.
Claim 11
Dependent Claim
23 words
a second transistor amplifier driven by the output of said first transistor amplifier to provide an in-phase feedback signal to said tank circuit.
Claim 12
Dependent Claim
61 words
a second inductance in the tank circuit of an oscillator, said oscillator being normally operative when connected to a source of direct current power to generate an unmodulated high-frequency output signal, and operative in response to the coupling of said first inductance of said keying network to said second inductance of said tank circuit to generate a modulated high-frequency output signal;
Claim 13
Dependent Claim
61 words
a second inductance in the tank circuit of an oscillator, said oscillator being normally operative when connected to a source of direct current power to generate an unmodulated high-frequency output signal, and operative in response to the coupling of said first inductance of said keying network to said second inductance of said tank circuit to generate a modulated high-frequency output signal;
Claim 14
Dependent Claim
17 words
a radio-frequency detection circuit operative to provide an output corresponding to the envelope of the oscillator output;
Claim 15
Dependent Claim
17 words
a radio-frequency detection circuit operative to provide an output corresponding to the envelope of the oscillator output;
Claim 16
Dependent Claim
28 words
bias means operative to continuously cause fluctuations in the value of said current- and voltage-controlled variable capacitance when said first inductance is coupled to said keyable circuit means.
Claim 17
Dependent Claim
28 words
bias means operative to continuously cause fluctuations in the value of said current- and voltage-controlled variable capacitance when said first inductance is coupled to said keyable circuit means.
Claim 18
Dependent Claim
12 words
The control circuit according to claim 2 wherein said bias means comprises:
Claim 19
Dependent Claim
18 words
a low-frequency alternating-current amplifier operative to amplify only the alternating current components of said detection circuit output; and
Claim 20
Dependent Claim
18 words
a low-frequency alternating-current amplifier operative to amplify only the alternating current components of said detection circuit output; and
Claim 21
Dependent Claim
40 words
The control circuit according to claim 2 wherein said passive keying network means further comprises a second, variable capacitance connected in parallel with said first inductance to enable adjustment of the range of resonant frequencies of said keying network means.
Claim 22
Dependent Claim
22 words
A conversion circuit operative to convert the alternating current output of said low frequency alternating current amplifier to a direct current output.
Claim 23
Dependent Claim
22 words
A conversion circuit operative to convert the alternating current output of said low frequency alternating current amplifier to a direct current output.
Claim 24
Dependent Claim
41 words
The control circuit according to claim 1 wherein said keyable circuit means comprises an oscillator including a tank circuit having a second inductance, at least a portion of said second inductance being disposed for coupling with said passive keying network means.
Claim 25
Dependent Claim
15 words
The control circuit according to claim 5 wherein said oscillator includes a feedback loop comprising:
Claim 26
Dependent Claim
23 words
The control circuit according to claim 6 wherein the output of said first transistor amplifier comprises the output of said keyable circuit means.
Claim 27
Dependent Claim
37 words
The control circuit according to claim 6 wherein the output of said second transistor amplifier is maintained constant regardless of variations in the output of said first transistor amplifier by driving said second transistor amplifier to saturation.
Claim 28
Dependent Claim
24 words
The control circuit according to claim 5, further comprising detection means operative to produce an output corresponding to the envelope of the oscillator output.
Claim 29
Dependent Claim
26 words
The control circuit according to claim 9, further comprising amplifier means operative to amplify only the alternating current components of said output of said detection means.
Claim 30
Dependent Claim
27 words
The control circuit according to claim 10, further comprising conversion means operative to convert the alternating current output of said amplifier means to a direct current output.
Claim 31
Dependent Claim
5 words
An induction-keyed control circuit comprising:
Claim 32
Dependent Claim
5 words
An induction-keyed control circuit comprising:
References Cited (Backward Citations)
US3469204A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-14 | 1978-04-15 | 1978-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-14 | 1982-04-15 | 1982-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-14 | 1986-04-15 | 1986-10-15 | $7700.00 | Window Closed / Lapsed |