US3444474A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Active equalizer circuit
Assignee: AT&T Inc
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Filing: 1965-12-10
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Granted: 1969-05-13
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Expires: 1985-12-10
Abstract
No abstract record available.
Inventors
- 👤 David P Borenstein
- 👤 Arden B Wright
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:37
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/04; H04B3/14; H03; H03H; H03H11/00; H03H11/02; H03H11/04; H03H11/12; H03H11/1213; H04B3/141; H04B3/143; H04B3/145
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
64 words
AN EQUALIZER COMPRISING: AN AMPLIFIER, MEANS FOR ENERGIZING SAID AMPLIFIER; A FIRST POTENTIOMETER HAVING FIRST AND SECOND FIXED TERMINALS AND A VARIABLE CONTACT, SAID FIRST FIXED TERMINAL CONNECTED TO SAID AMPLIFIER; A SECOND POTENTIOMETER HAVING FIRST AND SECOND FIXED TERMINALS AND A VARIABLE CONTACT; CAPACITOR MEANS CONNECTED BETWEEN SAID FIRST FIXED TERMINAL OF SAID SECOND POTENTIOMETER AND THE VARIABLE CONTACT OF SAID FIRST POTENTIOMETER;
Claim 2
Dependent Claim
64 words
AN EQUALIZER COMPRISING: AN AMPLIFIER, MEANS FOR ENERGIZING SAID AMPLIFIER; A FIRST POTENTIOMETER HAVING FIRST AND SECOND FIXED TERMINALS AND A VARIABLE CONTACT, SAID FIRST FIXED TERMINAL CONNECTED TO SAID AMPLIFIER; A SECOND POTENTIOMETER HAVING FIRST AND SECOND FIXED TERMINALS AND A VARIABLE CONTACT; CAPACITOR MEANS CONNECTED BETWEEN SAID FIRST FIXED TERMINAL OF SAID SECOND POTENTIOMETER AND THE VARIABLE CONTACT OF SAID FIRST POTENTIOMETER;
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-05-12 | 1972-11-11 | 1973-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-05-12 | 1976-11-11 | 1977-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-05-12 | 1980-11-11 | 1981-05-13 | $7700.00 | Window Closed / Lapsed |