US3914743A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Data system multibranch junction circuit having branch line selection
Assignee: AT&T Inc
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Filing: 1972-11-24
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Granted: 1975-10-21
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Expires: 1992-11-24
Abstract
Abstract A multipoint hub or junction unit has a main channel connected to a control station of a selective calling line and a plurality of branch lines, certain of the branch lines connected to downstream line stations and one branch line connected to a main channel of a downstream multipoint junction unit whose branches are connected to other line stations. Normally, downstream data signals from the control station are split by the hub and broadcast to all the branches, the signals to the downstream hub being split again. Upstream transmission on each branch is combined and propagates to the main line. The multipoint junction unit normally blocks upstream supervisory signals. When branch lines are to be tested, signaling equipment is connected into the main line and signals the hub to block all its branches, to select blocked branches to be tested and to unblock the selected branches to permit passage of upstream and downstream data and supervisory signals.
Inventors
- 👤 Scott Mcdowell Fitch
- 👤 Leo Michael Kolensky
- 👤 Joseph Conrad Panek
- 👤 David Charles Rife
- 👤 Walter Rudolph Schaefer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:34
CPC Classifications
H; H04; H04L; H04L12/00
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
125 words
A junction circuit terminating a main line and a plurality of branch lines and having means for broadcasting data words and control words from the main line to all of the branch lines and means for controlling the passage of data words and control words from each of the branch lines to the main line characterized in that the passage controlling means normally enables the passage of data words and blocks the passage of control words and there is further included means responsive to branch line selection signals from the main line for changing the enabling and blocking operation of the passage controlling means of selected branch lines and differently changing the enabling and blocking operation of the passage controlling means of unselected branch lines.
Claim 2
Dependent Claim
125 words
A junction circuit terminating a main line and a plurality of branch lines and having means for broadcasting data words and control words from the main line to all of the branch lines and means for controlling the passage of data words and control words from each of the branch lines to the main line characterized in that the passage controlling means normally enables the passage of data words and blocks the passage of control words and there is further included means responsive to branch line selection signals from the main line for changing the enabling and blocking operation of the passage controlling means of selected branch lines and differently changing the enabling and blocking operation of the passage controlling means of unselected branch lines.
Claim 3
Dependent Claim
45 words
A junction circuit in accordance with claim 1 wherein the operation changing means includes means responsive to the branch selection signals from the main line for precluding passage of data words and control words from unselected ones of the branch lines to the main line.
Claim 4
Dependent Claim
70 words
A junction circuit in accordance with claim 1 wherein the operation changing means includes means responsive to initial ones of the selection signals for precluding passage of data words and control words from all of the branch lines to the main line and means responsive to subsequent ones of the selection signals for selecting enabling passage of data words and control words from each selected branch to the main line.
Claim 5
Dependent Claim
41 words
A junction circuit in accordance with claim 3 wherein there is further included means responsive to the initial ones of the selection signals for blocking the broadcast of data words and control words from the main line to the branch lines.
Claim 6
Dependent Claim
41 words
A junction circuit in accordance with claim 4 wherein there is further included means responsive to the subsequent selection signals for permitting passage of data words and control words from the main line to the selected ones of the branch lines.
Claim 7
Dependent Claim
33 words
A junction circuit in accordance with claim 1 wherein the operations changing means includes means for permitting the passage of data words and control words from the selected ones of the branch lines.
Claim 8
Dependent Claim
27 words
A junction circuit in accordance with claim 3 wherein the precluding means includes means for sending data signals identifying the junction circuit back to the main line.
Claim 9
Dependent Claim
27 words
A junction circuit in accordance with claim 3 wherein the enabling means includes means for sending data signals identifying the selected branch back to the main line.
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) | 1978-10-20 | 1979-04-21 | 1979-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-20 | 1983-04-21 | 1983-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-20 | 1987-04-21 | 1987-10-21 | $7700.00 | Window Closed / Lapsed |