US3368167A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for equalizing a transmission system
Assignee: AT&T Inc
•
Filing: 1965-05-07
•
Granted: 1968-02-06
•
Expires: 1985-05-07
Abstract
No abstract record available.
Inventors
- 👤 Robert S Graham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:27
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/04; H04B3/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
153 words
IN COMBINATION, A TRANSMISSION CHANNEL INCLUDING A MAIN STATION AND A REMOTE STATION, AN EQUALIZER CONNECTED WITH SAID CHANNEL AT SAID REMOTE LOCATION, A DIGITAL MEMORY CIRCUIT AT SAID REMOTE LOCATION, A DIGITAL TO ANALOG CONVERTER AT SAID REMOTE LOCATION, MEANS AT SAID REMOTE STATION TO CONNECT SAID DIGITAL MEMORY CIRCUIT TO SAID DIGITAL TO ANALOG CONVERTER, MEANS AT SAID MAIN STATION FOR GENERATING A COMMOND SIGNAL AND FOR APPLYING SAID COMMAND SIGNAL TO SAID CHANNEL, RECEIVING MEANS AT SAID REMOTE LOCATION FOR CHANGING THE STATE OF SAID DIGITAL MEMORY CIRCUIT IN RESPONSE TO SAID COMMAND SIGNAL, MEANS FOR VARYING THE OUTPUT OF SAID DIGITAL TO ANALOG CONVERTER AS SAID DIGITAL MEMORY CIRCUIT CHANGES STATE, CONTROL ELEMENT INTERCONNECTED WITH SAID EQUALIZER FOR ADJUSTING THE FREQUENCY RESPONSE OF SAID EQUALIZER, AND MEANS FOR PERIODICALLY VARYING THE IMPEDANCE OF SAID CONTROL ELEMENT IN RESPONSE TO CHANGES IN THE OUTPUT OF SAID DIGITAL TO ANALOG CONVERTER.
Claim 2
Dependent Claim
153 words
IN COMBINATION, A TRANSMISSION CHANNEL INCLUDING A MAIN STATION AND A REMOTE STATION, AN EQUALIZER CONNECTED WITH SAID CHANNEL AT SAID REMOTE LOCATION, A DIGITAL MEMORY CIRCUIT AT SAID REMOTE LOCATION, A DIGITAL TO ANALOG CONVERTER AT SAID REMOTE LOCATION, MEANS AT SAID REMOTE STATION TO CONNECT SAID DIGITAL MEMORY CIRCUIT TO SAID DIGITAL TO ANALOG CONVERTER, MEANS AT SAID MAIN STATION FOR GENERATING A COMMOND SIGNAL AND FOR APPLYING SAID COMMAND SIGNAL TO SAID CHANNEL, RECEIVING MEANS AT SAID REMOTE LOCATION FOR CHANGING THE STATE OF SAID DIGITAL MEMORY CIRCUIT IN RESPONSE TO SAID COMMAND SIGNAL, MEANS FOR VARYING THE OUTPUT OF SAID DIGITAL TO ANALOG CONVERTER AS SAID DIGITAL MEMORY CIRCUIT CHANGES STATE, CONTROL ELEMENT INTERCONNECTED WITH SAID EQUALIZER FOR ADJUSTING THE FREQUENCY RESPONSE OF SAID EQUALIZER, AND MEANS FOR PERIODICALLY VARYING THE IMPEDANCE OF SAID CONTROL ELEMENT IN RESPONSE TO CHANGES IN THE OUTPUT OF SAID DIGITAL TO ANALOG CONVERTER.
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) | 1971-02-05 | 1971-08-07 | 1972-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-02-05 | 1975-08-07 | 1976-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-02-05 | 1979-08-07 | 1980-02-06 | $7700.00 | Window Closed / Lapsed |