IT1108170B - Testing telephone lines to determine electrical characteristics
- Google Patents
Testing telephone lines to determine electrical characteristics
Info
Publication number
IT1108170B
IT1108170BIT68145/78AIT6814578AIT1108170BIT 1108170 BIT1108170 BIT 1108170BIT 68145/78 AIT68145/78 AIT 68145/78AIT 6814578 AIT6814578 AIT 6814578AIT 1108170 BIT1108170 BIT 1108170B
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Teradyne IncfiledCriticalTeradyne Inc
Priority to IT68145/78ApriorityCriticalpatent/IT1108170B/en
Publication of IT7868145A0publicationCriticalpatent/IT7868145A0/en
Application grantedgrantedCritical
Publication of IT1108170BpublicationCriticalpatent/IT1108170B/en
A two-wired telephone testing system uses a 1f. test signal which is a multiple of the power line frequency. This test signal is applied between the two-wires or between either wire at a point of potential reference (ground). A measure of the integrated value of the current between the connected points is then made for a period equal to one-half cycle of the applied signal with one polarity and one-half cycle with the polarity of the measured signal reversed. The integration periods are selected to be in phase with the applied signal for determining conductance and 90 deg. out of phase for determining susceptance. DC; measurement can also be made for the same time periods.
IT68145/78A1978-05-181978-05-18Testing telephone lines to determine electrical characteristics
IT1108170B
(en)
Testing telephone lines to determine electrical characteristics - using LF test signal between two wires or between either wire and earth for fault detection and location
Testing telephone lines to determine electrical characteristics - using LF test signal between two wires or between either wire and earth for fault detection and location