US3745529A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Trouble alarm device for transmission system
Assignee: DECISION DATA Inc A CORP OF
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Filing: 1971-12-27
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Granted: 1973-07-10
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Expires: 1991-12-27
Abstract
Abstract In association with a data terminal having provision for receiving or locally generating data signals and translating the signals into video signals to cause the symbols represented by the signals to be displayed on a cathode ray tube, a communication channel assurance system is disclosed. The system comprises a video signal inversion device controlled by a timer that monitors the communication channel for the presence of incoming data signals. Such signals repetitiously recycle the timer, but upon a cessation of signals for a predetermined interval the timer times out and causes inversion of video signals, thereby reversing the symbol and background tones of the display on the cathode ray tube.
Inventors
- 👤 R Engle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:47
CPC Classifications
G; G06; G06F; G06F11/00; G06F11/07; G06F11/0703; G06F11/0751; G06F11/0754; G06F11/0757; G09; G09G; G09G1/00; G09G1/28
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
114 words
A data receiving station comprising: means for receiving digital data signals; means controlled by said signal receiving means for converting digital signals to video signals; and cathode ray tube means for displaying symbols represented by said video signals wherein the improvement comprises: means interposed between said converting means and said cathode ray tube means for presenting for utilization by the cathode ray tube means two versions of said video signals one of which is an inversion of the other; and means for selecting one or the other of said versions of the video signals for presentation to said cathode ray tube means as an indicator of a predetermined status of the signal receiving means.
Claim 2
Dependent Claim
114 words
A data receiving station comprising: means for receiving digital data signals; means controlled by said signal receiving means for converting digital signals to video signals; and cathode ray tube means for displaying symbols represented by said video signals wherein the improvement comprises: means interposed between said converting means and said cathode ray tube means for presenting for utilization by the cathode ray tube means two versions of said video signals one of which is an inversion of the other; and means for selecting one or the other of said versions of the video signals for presentation to said cathode ray tube means as an indicator of a predetermined status of the signal receiving means.
Claim 3
Dependent Claim
18 words
A combination in accordance with claim 1 wherein the selecting means is controlled by received digital data signals.
Claim 4
Dependent Claim
50 words
A combination in accordance with claim 1 wherein said selecting means includes a timing device controlled by received signals so as to cause the selecting means to select a predetermined one of the two versions of said video signals until cessation of signals for an interval exceeding a predetermined duration.
Claim 5
Dependent Claim
34 words
A combination in accordance with claim 3 wherein said timing device is a monostable two-state device connected to the digital signal receiving means to be settable to its unstable state by received digital signals.
Claim 6
Dependent Claim
38 words
A combination in accordance with claim 4 wherein received digital signals repetitiously reset said two-state device to its full timing interval to qualify it to monitor said digital signal receiving means for signal cessations exceeding said predetermined interval.
Claim 7
Dependent Claim
50 words
A combination in accordance with claim 1 wherein: said means for presenting two versions of said video signals comprises two video signal transmission paths each including a gate controlled by said selecting means so that the selecting means enables one or the other of the gates to pass video signals.
Claim 8
Dependent Claim
43 words
A combination in accordance with claim 6 wherein one of said video signal transmission paths includes preceding The gate therein an odd number of inverters for presenting to its associated gate the inversion of the signal on the other video signal transmission path.
Claim 9
Dependent Claim
43 words
A combination in accordance with claim 6 including an OR gate having its inputs connected to the outputs of the gates in said two video signal transmission paths for passing video signals from either of those gates to said cathode ray tube means.
Claim 10
Dependent Claim
25 words
A combination in accordance with claim 2 having manually operable means for controlling said selecting means independently of received digital signals for checking its operativeness.
Claim 11
Dependent Claim
36 words
Apparatus in accordance with claim 4 including a manually operable key and a pulse differentiating network for pulsing said two-state device independently of received digital signals for checking the operativeness of the video signal inverting system.
Claim 12
Dependent Claim
157 words
A data receiving station comprising: means for receiving digital data signals; means controlled by said signal receiving means for converting digital signals to video signals; and cathode ray tube means for displaying symbols represented by said video signals wherein the improvement comprises: a timing device monitoring the operation of said signal receiving means and having one operative condition during signal reception at a predetermined minimum rate and another operative condition upon cessation of signals for an interval exceeding a predetermined duration; means interposed between said converting means and said cathode ray tube means for deriving for utilization by the cathode ray tube means two versions of said video signals one of which is an inversion of the other; and means controlled by said timing means in accordance with one or the other of its two operative conditions for passing one or the other of said two versions of said video signals to said cathode ray tube means.
Claim 13
Dependent Claim
157 words
A data receiving station comprising: means for receiving digital data signals; means controlled by said signal receiving means for converting digital signals to video signals; and cathode ray tube means for displaying symbols represented by said video signals wherein the improvement comprises: a timing device monitoring the operation of said signal receiving means and having one operative condition during signal reception at a predetermined minimum rate and another operative condition upon cessation of signals for an interval exceeding a predetermined duration; means interposed between said converting means and said cathode ray tube means for deriving for utilization by the cathode ray tube means two versions of said video signals one of which is an inversion of the other; and means controlled by said timing means in accordance with one or the other of its two operative conditions for passing one or the other of said two versions of said video signals to said cathode ray tube means.
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) | 1976-07-09 | 1977-01-08 | 1977-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-09 | 1981-01-08 | 1981-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-09 | 1985-01-08 | 1985-07-10 | $7700.00 | Window Closed / Lapsed |