US3816663A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Real-time multiplexed digital data recording system for telephone central office ama recorders
Assignee: EH RES LAB Inc
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Filing: 1972-11-02
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Granted: 1974-06-11
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Expires: 1992-11-02
Abstract
Abstract A real-time multiplexed digital data recording system for replacing one to ten AMA paper perforators of a telephone central office with a magnetic tape system. The system provides a deskewing technique for interfacing with the electromagnetic actuating pulses of the AMA recorder and also provides for reverse reading of the magnetic tape to detect disconnect characters while at the same time maintaining compatability with a standard multi-channel magnetic tape reader.
Inventors
- 👤 P Goodale
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:30
CPC Classifications
H; H04; H04M; H04M15/00; H04M15/04
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
142 words
A real-time multiplexed digital data recording system for telephone central office automatic message accounting (AMA) recorders, such recorders monitoring a predetermined number of trunks and providing parallel data on a plurality of output lines related to calls placed on said trunks said system comprising: means responsive to a preselected group of output lines for indicating the presence of data on at least one of said lines; time delay means responsive to said indication of the presence of data for providing a load command a predetermined time after said indication; and memory means for sampling and storing said parallel data from all of said plurality of output lines in response to a load command from said time delay means said sampling of said data occurring in a time interval which is relatively short compared to said predetermined time of said time delay means.
Claim 2
Dependent Claim
142 words
A real-time multiplexed digital data recording system for telephone central office automatic message accounting (AMA) recorders, such recorders monitoring a predetermined number of trunks and providing parallel data on a plurality of output lines related to calls placed on said trunks said system comprising: means responsive to a preselected group of output lines for indicating the presence of data on at least one of said lines; time delay means responsive to said indication of the presence of data for providing a load command a predetermined time after said indication; and memory means for sampling and storing said parallel data from all of said plurality of output lines in response to a load command from said time delay means said sampling of said data occurring in a time interval which is relatively short compared to said predetermined time of said time delay means.
Claim 3
Dependent Claim
20 words
A system as in claim 1 together with scanning means for sequentially sampling data from a plurality of AMA recorders.
Claim 4
Dependent Claim
35 words
A system as in claim 1 where said means responsive to a preselected group of data lines includes filter means having a relatively slow risetime for preventing spurious noise pulses from giving false data indications.
Claim 5
Dependent Claim
14 words
A system as in claim 3 where said filter means includes an RC circuit.
Claim 6
Dependent Claim
44 words
A system as in claim 3 where said means responsive to a preselected group of data lines includes Schmitt trigger means coupled to said filter means for providing an output signal during the presence of data on any of said group of data lines.
Claim 7
Dependent Claim
55 words
A system as in claim 1 where said means responsive to a preselected group of data lines includes Schmitt trigger means for providing an output signal only during the presence of data on any of said group of data lines and includes flip-flop means enabled by said output signal and reset by said load command.
Claim 8
Dependent Claim
17 words
A system as in claim 6 where said flip-flop means is activated by said time delay means.
Claim 9
Dependent Claim
15 words
A system as in claim 1 where said time delay means is a one-shot multivibrator.
Claim 10
Dependent Claim
13 words
A system as in claim 1 where said predetermined time is 30 milliseconds.
Claim 11
Dependent Claim
77 words
A system as in claim 1 together with multichannel recording means including magnetic tape for recording said data stored in said memory means, said recording means including means for recording a pseudo longitudinal redundancy check (LCR) character on said magnetic tape, for use when said tape is read in a reverse direction, and for later recording a simulated data character on said tape for validating said LRC character when said tape is read in a reverse direction.
Claim 12
Dependent Claim
72 words
A system as in claim 10 where said means for recording said simulated data character includes a plurality of write flip-flops associated with the channels of said recording means for writing on said magnetic tape, means for setting all of said flip-flops to the same state for providing said LRC character and means for resetting said flip-flops in response to the last character of true data to provide said simulated data character.
Claim 13
Dependent Claim
120 words
A real-time multiplexed digital data recording system for telephone central office automatic message accounting recorders, such recorders monitoring a predetermined number of trunks and providing parallel data on a plurality of output lines related to calls placed on said trunks said system comprising: means for sampling and storing said parallel data; multi-channel recording means including magnetic tape for recording said data stored in said memory means said recording means including means for recording a pseudo longitudinal redundancy check (LRC) character on said magnetic tape, for use when said tape is read in a reverse direction, and for later recording a simulated data character on said tape for validating said LRC character when said tape is read in a reverse direction.
Claim 14
Dependent Claim
120 words
A real-time multiplexed digital data recording system for telephone central office automatic message accounting recorders, such recorders monitoring a predetermined number of trunks and providing parallel data on a plurality of output lines related to calls placed on said trunks said system comprising: means for sampling and storing said parallel data; multi-channel recording means including magnetic tape for recording said data stored in said memory means said recording means including means for recording a pseudo longitudinal redundancy check (LRC) character on said magnetic tape, for use when said tape is read in a reverse direction, and for later recording a simulated data character on said tape for validating said LRC character when said tape is read in a reverse direction.
Claim 15
Dependent Claim
71 words
A system as in claim 12 where said means for recording said simulated data characters includes a plurality of write flip-flops associated with the channels of said recording means for writing on said tape, means for setting all of said flip-flops to the same state for providing said LRC character and means for resetting said flip-flops in response to the last character of true data to provide said simulated data character.
Claim 16
Dependent Claim
22 words
A system as in claim 12 where said recording means records said pseudo LRC character in the inter-record gap of said tape.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-10 | 1977-12-10 | 1978-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-10 | 1981-12-10 | 1982-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-10 | 1985-12-10 | 1986-06-11 | $7700.00 | Window Closed / Lapsed |