摘要:
A digital telephone circuit is transferred from an old line to a new line. Before the transfer, a first stage delay circuit is inserted, wherein the delay of the data is incrementally adjusted to match the delay of a data control element. The data control element is then inserted in series with the data on the old line. The data control element incrementally adjust the delay and amplitude of the data on the old line to match that of the data on the new line. The incremental adjustments to delay and amplitude are within the specifications of the circuit, so as to minimize interruptions to the circuit. Interruptions are also minimized when the circuit is transferred to the new line. The data control element also introduces variations into the data at an upstream location. These are detected at a downstream location and are used for testing and communication purposes. The variations are removed from the data at the downstream end. The new line is used for communications between the transfer locations before the transfer. After the transfer occurs, the old line is used for communications.
摘要:
Resistive faults are analyzed on a conductor in a telephone line by first charging the conductor to an initial voltage. The conductor is allowed to float for a finite amount of time, allowing some of the charge on the conductor to leak through any resistive fault. Then, the voltage of the conductor is measured and compared to the initial voltage. Loss of voltage indicates a resistive fault. This information can be used to provide an indication of the accuracy of a capacitance measurement and can be used to correct the capacitance measurement to account for the error due to the resistive fault.
摘要:
A passive electrical marker has tuned circuits, each of which includes a coil and a capacitance. The tuned circuits are oriented with respect to each other in a predetermined arrangement so as to provide a broader spatial response. A foamed core inside of the tuned circuits maintains the tuned circuits in their respective orientations and protects the tuned circuits from mechanical shock. A shell or housing around the foamed tuned circuits provides environmental protection to the tuned circuits. The tuned circuits can be foamed together in a mold and then placed into the housing. Alternatively, the tuned circuits can be foamed together inside of a housing, which housing maintains the orientations between the tuned circuits during foaming. As still another alternative, the housing can be applied to the outside of the foamed tuned circuits as a coating.
摘要:
A probe for use in sampling signals from a pair of telephone wires has two conductors that are separated from each other by an insulating material such as a circuit board. Each of the conductors has an overall size and has plural nonconductive interstices therein so as to reduce the capacitance of the probe. In one embodiment, each of the conductors is shaped like a comb having conductive strips. Each of the conductors could alternatively be shaped in a zig zag manner. The telephone wires are oriented parallel to the strips so as to enhance coupling therebetween. The probe can have plural channels thereon, such as two conductors on each side of the insulating material. The strips of one conductor are located in the gaps of the other conductor which on the same side of the insulating material. The probe can reduce common mode noise by being balanced. A grounded guard trace on each side of the insulating material snubs homogeneous electric fields.
摘要:
A method and an apparatus for detecting signals in an electromagnetically noisy environment by detecting electromagnetic signals comprising a noise signal and a known signal, and compressing the electromagnetic signal to thereby generate a compressed signal. The compressed signal is filtered to generate a filtered signal comprising substantially the known signal, and the filtered signal is expanded.
摘要:
A fall of potential method of determining earth ground resistance which utilizes an earth ground tester and eliminates the need for utilizing removable ground stakes. Rather than utilizing a “far stake” the method provides connection of the earth ground tester to the telephone wires. Rather than utilizing a “near stake” the method provides for connection of the earth ground tester to the cable shield.
摘要:
A fall of potential method of determining earth ground resistance which utilizes an earth ground tester and eliminates the need for utilizing removable ground stakes. Rather than utilizing a “far stake” the method provides connection of the earth ground tester to the telephone wires. Rather than utilizing a “near stake” the method provides for connection of the earth ground tester to the cable shield.