Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
146 words
Surge protection means for a signal transmission system having a plurality of transmission lines each comprising a pair of conductors, said protection means comprising: a first diode bridge having two cathode-anode nodes, each to be connected to a respective one of said pair of conductors of one transmission line; a second diode bridge having two cathode-anode nodes each to be connected to a respective one of the pair of conductors of a second transmission line and; a pair of surge diverter devices, one interconnecting a cathode-cathode node of said first bridge and an anode-anode node of said second bridge, the other device interconnecting an anode-anode node of said first bridge and a cathode-cathode node of said second bridge, said surge diverter devices being adapted to switch from a high impedance state to a low impedance state when the voltage across the device exceeds a predetermined level.
Claim 2
Dependent Claim
146 words
Surge protection means for a signal transmission system having a plurality of transmission lines each comprising a pair of conductors, said protection means comprising: a first diode bridge having two cathode-anode nodes, each to be connected to a respective one of said pair of conductors of one transmission line; a second diode bridge having two cathode-anode nodes each to be connected to a respective one of the pair of conductors of a second transmission line and; a pair of surge diverter devices, one interconnecting a cathode-cathode node of said first bridge and an anode-anode node of said second bridge, the other device interconnecting an anode-anode node of said first bridge and a cathode-cathode node of said second bridge, said surge diverter devices being adapted to switch from a high impedance state to a low impedance state when the voltage across the device exceeds a predetermined level.
Claim 3
Dependent Claim
29 words
Surge protection means as claimed in claim 1, wherein said one transmission line and said second transmission line are coupled to input and output terminals, respectively, of one amplifier.
Claim 4
Dependent Claim
36 words
Surge protection means as claimed in claim 2, wherein said one amplifier has associated therewith power extraction means for deriving from at least one of said one and second transmission lines power to supply said amplifier.
Claim 5
Dependent Claim
64 words
Surge protection means as claimed in claim 2, wherein said one and said second transmission lines are coupled, respectively, to the input of one amplifier and the output of a second amplifier arranged to convey signals oppositely to said one amplifier, a further pair of transmission lines being coupled to, respectively, the output of said one amplifier and the input of said second amplifier.
Claim 6
Dependent Claim
27 words
Surge protection means as claimed in claim 4, including power extraction means connected between said one and second lines to derive therefrom power to supply both amplifiers.
Claim 7
Dependent Claim
41 words
Surge protection means as claimed in claim 2, including a resistance in series between the cathode-anode node of one of said first diode bridge and said second diode bridge and the terminal of said amplifier to which that node is coupled.
Claim 8
Dependent Claim
72 words
A signal transmission system comprising a plurality of transmission lines, each comprising a pair of conductors, and surge protection means as claimed in any one of claims 1 to 6, said first diode bridge having its cathode-anode nodes connected to respective conductors of one of said plurality of transmission lines and said second diode bridge having its cathode-anode nodes connected to respective conductors of a second of said plurality of transmission lines.