US3575556A
Expired / Lapsed
US
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Data transmission apparatus and methods
Assignee: Digitronics Corp
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Filing: 1967-11-13
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Granted: 1971-04-20
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Expires: 1987-11-13
Abstract
Abstract A data transmission system comprises a magnetic tape recorder, and a signal transmitter connected via a telephone channel and a signal receiver. The magnetic tape recorder includes a magnetic recording transducer which records characters as a combination of bits serially along the magnetic tape. The recorded character bits are interleaved with sprocket bits. The so recorded magnetic tape is then read to cause a signal transmitter to transmit tone signals via a telephone channel to a signal receiver.
Inventors
- 👤 Edgar Wolf
- 👤 Franics C Marino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 02:49
CPC Classifications
H; H04; H04L; H04L25/00; H04L25/02; H04L25/05
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
208 words
For combination with a telephone system which includes at least a first telephone adapted to receive a calling signal and a characteristic tone and to transmit information signals, and a second telephone adapted to transmit a calling signal and a characteristic tone and to receive information signals, information signal generating apparatus coupled to said first telephone comprising first means for sensing for a calling signal received by said first telephone, second means energized by said first means for permitting said first telephone to be connected to said second telephone when said calling signal is sensed, third means for sensing for the characteristic tone when received by the first telephone and for producing an actuating signal in response thereto, fourth means connected to said first and third means responsive to said actuating signal for deenergizing said second means prior to the transmission of any information signals if said actuating signal is not produced within a given period of time after the calling signal is sensed and being rendered disabled if said actuating signal is produced within said given period of time, and fifth means connected to said third means for initiating the transmission of information signals to the first telephone for transmission thereby in response to said actuating signal.
Claim 2
Dependent Claim
208 words
For combination with a telephone system which includes at least a first telephone adapted to receive a calling signal and a characteristic tone and to transmit information signals, and a second telephone adapted to transmit a calling signal and a characteristic tone and to receive information signals, information signal generating apparatus coupled to said first telephone comprising first means for sensing for a calling signal received by said first telephone, second means energized by said first means for permitting said first telephone to be connected to said second telephone when said calling signal is sensed, third means for sensing for the characteristic tone when received by the first telephone and for producing an actuating signal in response thereto, fourth means connected to said first and third means responsive to said actuating signal for deenergizing said second means prior to the transmission of any information signals if said actuating signal is not produced within a given period of time after the calling signal is sensed and being rendered disabled if said actuating signal is produced within said given period of time, and fifth means connected to said third means for initiating the transmission of information signals to the first telephone for transmission thereby in response to said actuating signal.
Claim 3
Dependent Claim
167 words
For combination with a telephone system which includes at least a first telephone adapted to receive a calling signal and a characteristic tone and to transmit information signals, and a second telephone adapted to transmit a calling signal and a characteristic tone and to receive information signals, information signal generating apparatus coupled to said first telephone comprising first means for sensing for a calling signal received by said first telephone, second means energized by said first means for permitting said first telephone to be connected to said second telephone when said calling signal is sensed, controllable timing means actuatable by said first means for deenergizing said second means a given period of time after actuation, third means for sensing for the characteristic tone when received by the first telephone, fourth means connected to said third means for transmitting information signals to the first telephone for transmission thereby after said characteristic tone is sensed, and fifth means responsive to said third means for disabling said controllable timing means.
Claim 4
Dependent Claim
167 words
For combination with a telephone system which includes at least a first telephone adapted to receive a calling signal and a characteristic tone and to transmit information signals, and a second telephone adapted to transmit a calling signal and a characteristic tone and to receive information signals, information signal generating apparatus coupled to said first telephone comprising first means for sensing for a calling signal received by said first telephone, second means energized by said first means for permitting said first telephone to be connected to said second telephone when said calling signal is sensed, controllable timing means actuatable by said first means for deenergizing said second means a given period of time after actuation, third means for sensing for the characteristic tone when received by the first telephone, fourth means connected to said third means for transmitting information signals to the first telephone for transmission thereby after said characteristic tone is sensed, and fifth means responsive to said third means for disabling said controllable timing means.
Claim 5
Dependent Claim
194 words
For combination with a telephone system which includes at least a first telephone adapted to receive a calling signal and a characteristic tone and to transmit information signals, and a second telephone adapted to transmit a calling signal and a characteristic tone and to receive information signals, information signal generating apparatus coupled to said first telephone comprising first means for sensing fOr a calling signal received by said first telephone, second means energized by said first means for permitting said first telephone to be connected to said second telephone when said calling signal is sensed, third means for sensing for the characteristic tone when received by the first telephone, fourth means connected to said third means for transmitting information signals to the first telephone for transmission thereby after the characteristic tone is sensed and fifth means connected to said first, third and fourth means for deenergizing said second means if the characteristic tone is not sensed a given period of time after the calling signal is sensed and, when said characteristic tone is sensed within said given period of time, if said fourth means does not transmit information signals during a predetermined time interval.
Claim 6
Dependent Claim
194 words
For combination with a telephone system which includes at least a first telephone adapted to receive a calling signal and a characteristic tone and to transmit information signals, and a second telephone adapted to transmit a calling signal and a characteristic tone and to receive information signals, information signal generating apparatus coupled to said first telephone comprising first means for sensing fOr a calling signal received by said first telephone, second means energized by said first means for permitting said first telephone to be connected to said second telephone when said calling signal is sensed, third means for sensing for the characteristic tone when received by the first telephone, fourth means connected to said third means for transmitting information signals to the first telephone for transmission thereby after the characteristic tone is sensed and fifth means connected to said first, third and fourth means for deenergizing said second means if the characteristic tone is not sensed a given period of time after the calling signal is sensed and, when said characteristic tone is sensed within said given period of time, if said fourth means does not transmit information signals during a predetermined time interval.
Claim 7
Dependent Claim
54 words
The apparatus of claim 3 wherein said fourth means comprises magnetic recording means including a magnetic tape upon which are recorded information signals, a magnetic reproducing head, a tape transport means for moving said magnetic tape operatively past said magnetic reproducing head, and means connected to said magnetic reproducing head for generating audible tones.
Claim 8
Dependent Claim
46 words
The apparatus of claim 4 wherein the information signals are sequentially occurring data signals and sprocket signals and said means for generating audible tones includes means for interleaving said sprocket signals and said data signals and so that the audible tones are shifted between two frequencies.
Claim 9
Dependent Claim
33 words
The apparatus of claim 5 wherein said fifth means includes means for deenergizing said second means if either a data signal or a sprocket signal does not occur during said predetermined time interval.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-19 | 1974-10-19 | 1975-04-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-19 | 1978-10-19 | 1979-04-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-19 | 1982-10-19 | 1983-04-20 | $7700.00 | Window Closed / Lapsed |