Abstract: A method of testing a communication line includes applying a voltage as a function of time on the communication line and measuring at least a first current and a second current flowing via the communication line. The second current is measured at a different point in time than the first current. The method includes deciding whether a given terminal element is connected to the communication line based on the first current and the second current.

Abstract: A method of testing a communication line includes applying a voltage as a function of time on the communication line. The function includes at least one ramp and at least one plateau. The method includes measuring a current flowing via the communication line, and calculating at least one electrical property of the communication line based on the voltage and the current.

Abstract: A system and method for testing a transmission line to a protected system includes measuring voltages between a tip-side node of an overcurrent protection device and the protected system, between a ring-side node of the overcurrent protection device and the protected system, between the tip of the transmission line and the protected system, and between the ring of the transmission line and the protected system. Using the measured voltages, the status of the overcurrent protection device and the overvoltage device may be recognized, and the magnitude of a voltage surge on either of the tip and ring wires may be determined.

Abstract: A system and method for testing a transmission line to a protected system includes measuring voltages between a tip-side node of an overcurrent protection device and the protected system, between a ring-side node of the overcurrent protection device and the protected system, between the tip of the transmission line and the protected system, and between the ring of the transmission line and the protected system. Using the measured voltages, the status of the overcurrent protection device and the overvoltage device may be recognized, and the magnitude of a voltage surge on either of the tip and ring wires may be determined.

Abstract: A signal generator is disclosed that generates a test signal to be applied to a first and second wire of a subscriber line. The signal generator is configured to generate the test signal at the first and second test signal outputs in a first time section such that a first potential at the first test signal output is changed from a first value to a second value and a second potential at the second test signal output is maintained constant at least during the change of the first potential. The signal generator is further configured to generate the test signal during a second time section such that the first potential at the first output and the second potential at the second output are oscillating with a predetermined frequency.

Abstract: A method of testing a communication line includes measuring a first voltage/current couple on the communication line, measuring a second voltage/current couple different from the first couple on the communication line, and calculating a resistance based on the first couple and the second couple.

Abstract: Embodiments related to line testing are described and depicted.

Abstract: The invention relates to a method for ascertaining a resistance value (Z) between a first contact (2) and a second contact (3) in a subscriber line interface circuit (4), where a protective circuit (9) for protecting the subscriber line interface circuit (4) against overvoltages is provided between the two contacts (2, 3) and comprises a parallel circuit containing a protective capacitor (5) with two resistors (7, 8) connected in series via a node (K), the node (K) being connected to a third contact (10) in the subscriber line interface circuit (4), where the method has the following steps: a predetermined charging voltage (UCharge) is applied to the protective capacitor (5); a threshold voltage (UTH) is calculated on the basis of the resistance values (R1, R2) of the two resistors (7, 8) and the applied charging voltage (UCharge); a measured voltage (UM) tapped off across one of the two resistors (7, 8) is measured while the protective capacitor (5) is discharging; the measured voltage (UM) is compared with

Abstract: The invention relates to a method and an apparatus for controlling a digital signal processor having a number of arithmetic units (1a, 1b) which process a program (8). A control unit (5) is provided for independent control of the individual arithmetic units (1a, 1b), which control unit (5) reads and evaluates the flags (9a, 9b) which are specific to the arithmetic units, and deactivates those arithmetic units (1a, 1b) whose associated flag is not set, so that a subroutine is carried out only by those arithmetic units (1a, 1b) whose flags are set.

Abstract: The invention provides a transmission apparatus (100) for transmission of electrical signals between a line driver (205), which is connected to a transmission line (201), and a switching center (301), having an analog feedback device (101) for coarse setting of a line voltage level (210) on the transmission line (201), and a digital feedback device (102), which is coupled to the analog feedback device (101) and has a feedback filter device (118), designed such that a filter input signal (404) can be converted to a filter output signal (405) at a rate which is lower than the sampling rate (fa) of an analog/digital converter (104).

Abstract: A method of testing a communication line includes applying a voltage as a function of time on the communication line and measuring at least a first current and a second current flowing via the communication line. The second current is measured at a different point in time than the first current. The method includes deciding whether a given terminal element is connected to the communication line based on the first current and the second current.

Abstract: A method of testing a communication line includes measuring a first voltage/current couple on the communication line, measuring a second voltage/current couple different from the first couple on the communication line, and calculating a resistance based on the first couple and the second couple.

Abstract: A method of testing a communication line includes applying a voltage as a function of time on the communication line. The function includes at least one ramp and at least one plateau. The method includes measuring a current flowing via the communication line, and calculating at least one electrical property of the communication line based on the voltage and the current.

Abstract: In the case of a device for transmission of telephone signals via a data telecommunications network (2) the analogue signals of a telephone terminal are converted to digital signals for transmission via the data telecommunications network (2) and/or, vice versa, digital signals from the data telecommunications network (2) are converted to analogue signals for transmission via the telephone terminal. In order to monitor the operation of the device, advantageously digital signals arising within the device are analyzed. According to the invention a digital signal is acquired within the device and the characteristics of this, which characterize the amplitude and/or the frequency response of the acquired digital signal, are determined. The determined characteristics are sent out via the data telecommunications network (2). In this way the function of such conversion devices can also be monitored over a greater distance via the data telecommunications network (2) and signals arising therein can be analyzed.

Abstract: A control circuit for generating a supply direct voltage for an analogue telephone comprises an SLIC circuit and a CODEC circuit. An analogue telephone is connectable to the SLIC circuit via a two-wire telephone line and the SLIC circuit detects a loop direct current flowing through the two-wire telephone line when connected to the SCLIC circuit. The CODEC circuit comprises a constant voltage source for generating a constant voltage and a subtractor for generating a differential voltage by subtracting a voltage proportional to the loop direct current from the constant voltage. The differential voltage is amplified with a constant gain factor for generating the supply direct voltage.

Abstract: A telephone system includes a controllable ringing generator for generating a ringing signal and an interface for providing a ringing voltage derived from that signal on the transmission line. The controllable ringing generator includes a control device for controlling the ringing voltage in response to the ringing current.

Abstract: A telephone system includes a transmission line for connection to at least one telephone and a telephone interface in communication with the transmission line. The telephone interface provides DC power when a telephone connected to the transmission line is in an off-hook state. A controller in communication with the telephone interface generates a pre-defined DC characteristic of the telephone interface, and a regulator in communication with the controller adaptively translates the DC characteristic.

Abstract: The invention relates to a method for ascertaining a resistance value (Z) between a first contact (2) and a second contact (3) in a subscriber line interface circuit (4), where a protective circuit (9) for protecting the subscriber line interface circuit (4) against overvoltages is provided between the two contacts (2, 3) and comprises a parallel circuit containing a protective capacitor (5) with two resistors (7, 8) connected in series via a node (K), the node (K) being connected to a third contact (10) in the subscriber line interface circuit (4), where the method has the following steps: a predetermined charging voltage (UCharge) is applied to the protective capacitor (5); a threshold voltage (UTH) is calculated on the basis of the resistance values (R1, R2) of the two resistors (7, 8) and the applied charging voltage (UCharge); a measured voltage (UM) tapped off across one of the two resistors (7, 8) is measured while the protective capacitor (5) is discharging; the measured voltage (UM) is compared with

Abstract: Transmission apparatus with variable impedance matching The invention provides a transmission apparatus (100) for transmission of electrical signals between a line driver (205), which is connected to a transmission line (201), and a switching center (301), having an analog feedback device (101) for coarse setting of a line voltage level (210) on the transmission line (201), and a digital feedback device (102), which is coupled to the analog feedback device (101) and has a feedback filter device (118), designed such that a filter input signal (404) can be converted to a filter output signal (405) at a rate which is lower than the sampling rate (fa) of an analog/digital converter (104).

Abstract: The invention relates to a method and an apparatus for controlling a digital signal processor having a number of arithmetic units (1a, 1b) which process a program (8). A control unit (5) is provided for independent control of the individual arithmetic units (1a, 1b), which control unit (5) reads and evaluates the flags (9a, 9b) which are specific to the arithmetic units, and deactivates those arithmetic units (1a, 1b) whose associated flag is not set, so that a subroutine is carried out only by those arithmetic units (1a, 1b) whose flags are set.