EP0016637A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Passive coupling arrangement and distributed data processing system including such arrangements
Assignee: Unisys Corp
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Filing: 1980-03-19
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Granted: —
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Expires: 2000-03-19
Abstract
Abstract A high impedance tap for use in distributed signal transmission systems, comprising microstrip circuit (100) which has conductor strips (101 and 103), located on an insulating substrate (102) and interconnecting the connectors (105). The substrate (102) also carries at least some of the high impedance components of the branch line. The new tap design eliminates some of the random factors which, in prior art taps, led to unsatisfactory matching of those taps to the transmission line. The specification also discloses a transceiver circuit for use with the tap and capable of receiving and transmitting low-level serial phase-modulated tri-state signals; and the configuration of a bus access module.
Inventors
- 👤 William Warren Davis
- 👤 Ernest Sharp Griffith
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 00:55
CPC Classifications
H; H04; H04L; H04L25/00; H04L25/02; H04L25/0264; H04L25/0266; H04L25/38; H04L25/40; H04L25/49; H04L25/4904
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
104 words
A passive tap for a signal transmission line, comprising a primary signal path arranged to be connected in series with the transmission line and having impedance characteristics substantially matching those of the transmission line, and a secondary signal path connected in parallel with, and presenting a high impedance to, the primary path, characterised in that the primary path comprises two strip conductors (101, 103) carried on and separated by an insulating substrate (102) which also carries connectors (105) included in the primary path for said series connection and at least some high impedance components (R 1 , R 3 ) of the secondary path.
Claim 2
Dependent Claim
104 words
A passive tap for a signal transmission line, comprising a primary signal path arranged to be connected in series with the transmission line and having impedance characteristics substantially matching those of the transmission line, and a secondary signal path connected in parallel with, and presenting a high impedance to, the primary path, characterised in that the primary path comprises two strip conductors (101, 103) carried on and separated by an insulating substrate (102) which also carries connectors (105) included in the primary path for said series connection and at least some high impedance components (R 1 , R 3 ) of the secondary path.
Claim 3
Dependent Claim
69 words
A passive tap according to claim 1 wherein the secondary path includes a network (D 1 , D 2 , -D 3 , D 4 ) arranged to conduct when the applied signal exceeds a predetermined magnitude during signal transmission to the primary path (101, 103, 105), and to be non-conducting when the signal level is below that threshold during signal reception from the primary path (101, 103, 105).
Claim 4
Dependent Claim
42 words
A passive tap as claimed in claim 2 wherein the network comprises two antiparallel branches of two or more series connected diodes (D 1 , D 2 , and D 3 , D 4 ) each, located on said insulating substrate (102).
Claim 5
Dependent Claim
86 words
A passive tap as claimed in claim 2 or claim 3, in which the network (D 1 , D 2 , D 3 , D 4 ) is connected in series with the secondary winding of a transformer to form the output circuit of a transmitter portion of a signal transceiver, and in which an input circuit of the transceiver comprises two matched high resistance voltage dividers (R 1 , R 2 and- R 3 , R 4 ) connected in parallel with the output circuit.
Claim 6
Dependent Claim
123 words
A passive tap as claimed in claim 4 wherein the signal transceiver coupled to the secondary current path is selectively operable in a receive mode or a transmit mode for receiving or transmitting serial phase-modulated signals and comprises a threshold detector (12) to detect when a received signal exceeds a preselected threshold and to produce a control signal in response thereto, a signal detector (27) coupled to the threshold detector (12) and arranged to produce a data signal in response to predetermined polarity changes in the received signal, and a lockout circuit (35) which holds the data and control signals at a preset level during operation of the transceiver in the transmit mode to render the receiver circuitry unresponsive to the transmitted signals.
References Cited (Backward Citations)
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