US3883832A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Single element controlled parallel-T audio network
Assignee: Individual
•
Filing: 1972-11-06
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Granted: 1975-05-13
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Expires: 1992-11-06
Abstract
Abstract A parallel-T audio frequency notch filter utilizing an additional resistive control element which when increased in resistive value forces the parallel-T to lower its maximum attenuation position along the frequency spectrum in accordance with said resistance changes.
Inventors
- 👤 James Wayne Fosgate
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 00:28
CPC Classifications
H; H03; H03H; H03H7/00; H03H7/01; H03H7/06; H03H7/065; H03H7/17; H03H7/1716; H03H7/1725
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
195 words
A single element controlled parallel-T network comprising: a pair of capacitors coupled together in series; a first conductor coupling said capacitors; a pair of fixed resistors coupled together in series; a second conductor coupling said resistors; a third resistor having one end thereof coupled to said first conductor between said capacitors; said third resistor having an opposite end; and a third capacitor having one side coupled to and between said pair of fixed resistors; said third capacitor having an opposite side; a third conductor coupling said opposite side of said third capacitor to said opposite end of said third resistor; and a variable resistor having one end coupled to said third conductor; said variable resistor having a second end; a first terminal coupling at said second end of said variable resistor; second and third terminal couplings at opposite sides of said first pair of capacitors from said first conductor; said fixed resistors having opposite ends from those connected to said second conductor; said last mentioned opposite ends coupled to respective ones of said second and third terminal couplings, whereby adjustment of said variable resistor may cause a change in frequency at which maximum attenuation occurs.
Claim 2
Dependent Claim
195 words
A single element controlled parallel-T network comprising: a pair of capacitors coupled together in series; a first conductor coupling said capacitors; a pair of fixed resistors coupled together in series; a second conductor coupling said resistors; a third resistor having one end thereof coupled to said first conductor between said capacitors; said third resistor having an opposite end; and a third capacitor having one side coupled to and between said pair of fixed resistors; said third capacitor having an opposite side; a third conductor coupling said opposite side of said third capacitor to said opposite end of said third resistor; and a variable resistor having one end coupled to said third conductor; said variable resistor having a second end; a first terminal coupling at said second end of said variable resistor; second and third terminal couplings at opposite sides of said first pair of capacitors from said first conductor; said fixed resistors having opposite ends from those connected to said second conductor; said last mentioned opposite ends coupled to respective ones of said second and third terminal couplings, whereby adjustment of said variable resistor may cause a change in frequency at which maximum attenuation occurs.
References Cited (Backward Citations)
US2503540A
Cited
US3794864A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-12 | 1978-11-11 | 1979-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-12 | 1982-11-11 | 1983-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-12 | 1986-11-11 | 1987-05-13 | $7700.00 | Window Closed / Lapsed |