Abstract: A telephone switchboard provides various operating voltages to a telephone in different operation modes. The telephone switchboard includes a control unit, an output control circuit and a voltage converter. The control unit detects the operation mode of a telephone and generates control signals to the output control unit. The output control unit controls direction of current flowing through the telephone according to the control signal, and generates a feedback signal according to any change in the operation mode of the telephone. The voltage converter receives the feedback signal and converts the received power to a suitable output operation voltage according to the feedback signal. The telephone switchboard is capable of providing various operation voltages to the telephone in the different operation modes.

Abstract: A telephone line testing device for use with a PABX having a plurality of input lines. The testing device includes test circuitry, a first connecting means for connection to a telephone line of a telephone system, a second connecting means for connection to a desired input line of the PABX, a first switch means for connecting either the PABX input line or the test circuitry to the telephone line. The test circuitry includes a test signal generating means for generating a test signal, a ringing signal detection means for detecting the presence of a ringing signal on the telephone line, and a second switch means which is responsive to the ringing signal detection means for automatically supplying a test signal generated by the test signal generating means to the telephone system when the test circuitry is connected to the telephone line by the first switch means and a ringing signal is desired.

Abstract: A telephone call processing system and method for providing operator service. The system maintains a number of customer directories, each customer directory having information pertaining to a number of subscribers of the customer. When an incoming telephone call is received by the system, the system automatically identifies the customer directory corresponding to the customer indicated by the telephone number dialed by the caller. Upon locating the appropriate customer directory, the system automatically switches access by the system operator thereto. Thereafter, the system operator may perform a search in the customer directory for the subscriber who the caller wishes to contact. Upon successfully locating information pertaining to the subscriber in the customer directory, the subscriber information may be communicated to the caller.

Abstract: An interactive electronic module (IEM) is adapted as a retrofit module for use in modular network equipment to provide real time analysis of trunk line signal performance and to detect trunk line signal faults, the IEM including a faceplate display panel accessible to the network operator for displaying the detected signal faults and for providing operator access to the IEM to command the display of selected trunk line faults.

Abstract: Method for replacing a first cable (1) by a second cable (2) between a first predetermined point (1a) and a second predetermined point (1b), comprising:a. the provision of first series impedance means (S1) close to the first end (2a) and second series impedance means (S2) close to the second end (2b) of the second cable (2), which first (S1) and second (S2) series impedance means can be switched between a state of high impedance value and a state of low impedance value;b. electrically connecting the second cable to the first cable (1) at the first (1a) and second (1b) points, during which operation both the first (S1) and the second (S2) series impedance means are kept in their state of high impedance value;c.

Abstract: A signal discrimination circuit for discriminating between a voice signal and a voiceband data signal that is transmitted over a telephone network. The signal discrimination circuit includes an electric power judgement unit, a zero-crossing number judgement unit, a sub-band power calculation unit, a tone detection unit, and a discriminated result output unit. The electric power judgement unit determines whether an input signal is a voice signal or a voiceband data signal based on an interblock electric power ratio of the input signal. The zero-crossing number judgement unit determines whether the input signal is a voice signal or a voiceband data signal based on a zero-crossing number of the input signal.

Abstract: The system has two units for transferring a telephone circuit from an old pair to a new pair between two locations. Each unit has a carrier amplitude measuring circuit to determine which location has the larger carrier amplitude and therefore which is the upstream location. Each unit has a charge switch, two transfer switches in the form of an old pair switch and a new pair switch and a controller for controlling the switches. One of the units closes its charge switch to charge the new pair to the dc level of the old pair. Then, the upstream unit operates its two transfer switches at the same time to switch from the old pair, by opening the old pair switch, to the new pair, by closing the new pair switch. The upstream unit transmits a signal to the downstream unit on a third pair. When the downstream unit receives the signal, it operates its two transfer switches at the same time to complete the transfer from the old pair to the new pair.

Abstract: A line unit, used in a line shelf having a line shelf processor and common logic, is provided with an EEPROM device for storing information relative to the line unit. The stored information includes line unit type identification codes, auto provisioning data, gain and equalization adjustment data and signaling translation tables. The data contained within the EEPROM may be utilized by the line shelf processor to provide automatic initialization and provisioning of the line unit when first inserted into the line shelf, and automatic signaling translation so that line unit signaling becomes compatible with a transmission facility connected to the line shelf. The need for factory preset resistors installed in the line unit may be eliminated by storing within the EEPROM a required gain setting.