US3586881A
Expired / Lapsed
US
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Transistor hybrid circuit
Assignee: AT&T Inc
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Filing: 1967-12-29
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Granted: 1971-06-22
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Expires: 1987-12-29
Abstract
Abstract A transistor hybrid circuit for exchanging signals between the incoming and outgoing paths of a four-wire line and a two-wire line is described. A signal from the incoming path is coupled via an amplifier and the base-emitter path of a coupling transistor to the two-wire line. An outgoing signal from the two-wire line is coupled via the emitter-collector path of the coupling transistor and a second amplifier to the outgoing path. A resistor network connected to the coupling transistor prevents the signal from the incoming path from being applied to the outgoing path.
Inventors
- 👤 Wilmer B Gaunt Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 09:06
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/38; H04B1/40; H04B1/54; H04B1/58; H04B1/586
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
171 words
A hybrid circuit for establishing signal transmission between the incoming and the outgoing paths of a four-wire line and a bidirectional two-wire line comprising first, second and third semiconductor devices each having first, second and control electrodes, an energy source, said first electrodes of said first and third devices being connected to said energy source, means for coupling said incoming path to the control electrode of said first device, means for coupling the second electrode of said third device to said outgoing path, mans for coupling said bidirectional two-wire line to the second electrode of saId second device, a network connected between the second electrode of said first device, and the second electrode of said third device and to the control electrode of said second device, the first electrode of said second device being connected to the control electrode of said third device, and impedance means connected between the second electrode of said first device and the first electrode of said second device for serially connecting said first and second devices.
Claim 2
Dependent Claim
171 words
A hybrid circuit for establishing signal transmission between the incoming and the outgoing paths of a four-wire line and a bidirectional two-wire line comprising first, second and third semiconductor devices each having first, second and control electrodes, an energy source, said first electrodes of said first and third devices being connected to said energy source, means for coupling said incoming path to the control electrode of said first device, means for coupling the second electrode of said third device to said outgoing path, mans for coupling said bidirectional two-wire line to the second electrode of saId second device, a network connected between the second electrode of said first device, and the second electrode of said third device and to the control electrode of said second device, the first electrode of said second device being connected to the control electrode of said third device, and impedance means connected between the second electrode of said first device and the first electrode of said second device for serially connecting said first and second devices.
Claim 3
Dependent Claim
200 words
A hybrid circuit for establishing signal transmission between an incoming path, an outgoing path and a bidirectional path comprising an incoming path coupling transistor, a bidirectional path coupling transistor, and an outgoing path coupling transistor, each transistor having a base, a collector and an emitter, a voltage source, the collectors of said incoming path coupling transistor and said outgoing path coupling transistor being connected to said voltage source, means for connecting said incoming path to the base of said incoming path coupling transistor, means for connecting the emitter of said outgoing path coupling transistor to said outgoing path, means for connecting said bidirectional path to the emitter of said bidirectional path coupling transistor, an impedance network directly connected between the emitter of said incoming path coupling transistor and the emitter of said outgoing path coupling transistor and to the base of said bidirectional path coupling transistor, the collector of said bidirectional path coupling transistor being directly connected to the base of said outgoing path coupling transistor, and impedance means connected between the emitter of said incoming path coupling transistor and the collector of said bidirectional path coupling transistor for serially connecting said incoming path and said bidirectional path coupling transistors.
Claim 4
Dependent Claim
200 words
A hybrid circuit for establishing signal transmission between an incoming path, an outgoing path and a bidirectional path comprising an incoming path coupling transistor, a bidirectional path coupling transistor, and an outgoing path coupling transistor, each transistor having a base, a collector and an emitter, a voltage source, the collectors of said incoming path coupling transistor and said outgoing path coupling transistor being connected to said voltage source, means for connecting said incoming path to the base of said incoming path coupling transistor, means for connecting the emitter of said outgoing path coupling transistor to said outgoing path, means for connecting said bidirectional path to the emitter of said bidirectional path coupling transistor, an impedance network directly connected between the emitter of said incoming path coupling transistor and the emitter of said outgoing path coupling transistor and to the base of said bidirectional path coupling transistor, the collector of said bidirectional path coupling transistor being directly connected to the base of said outgoing path coupling transistor, and impedance means connected between the emitter of said incoming path coupling transistor and the collector of said bidirectional path coupling transistor for serially connecting said incoming path and said bidirectional path coupling transistors.
Claim 5
Dependent Claim
23 words
A hybrid circuit according to claim 2 wherein each of said incoming path, bidirectional path and outgoing path transistors is an NPN transistor.
Claim 6
Dependent Claim
127 words
A hybrid circuit according to claim 2 wherein said impedance network comprises a voltage divider including a Zener diode having an anode and a cathode, said Zener diode cathode being connected to the emitter of said incoming path coupling transistor, a first impedance connected between said Zener diode anode and the base of said bidirectional path coupling transistor and a second impedance connected between the base of said bidirectional path coupling transistor, and the emitter of said outgoing path coupling transistor, and said impedance means connected between the emitter of said incoming path coupling transistor and the collector of said bidirectional path coupling transistor comprises a third impedance connected between the emitter of said incoming path coupling transistor and the collector of said bidirectional path coupling transistor.
Claim 7
Dependent Claim
35 words
A hybrid circuit according to claim 4 wherein said bidirectional path has a characteristic impedance, said third impedance is equal to twice said characteristic impedance, and said first impedance is equal to said second impedance.
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) | 1974-06-21 | 1974-12-21 | 1975-06-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-21 | 1978-12-21 | 1979-06-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-21 | 1982-12-21 | 1983-06-22 | $7700.00 | Window Closed / Lapsed |