Abstract: In a circuit arrangement for PCM telecommunication facilities, especially PCM long distance exchange facilities with several synchronous pulse clock controlled transmitters for common transmitting chanel, information from different transmission processes flows over a transmitting channel common to all transmitters. In addition to the transmitting channel, a test channel is provided. For the prevention of simultaneous transmission and a co-mingling together of information, each transmitter transmits its own binary coded address to the transmitting channel always before a message as well as to the test channel and receives back the total information after combining on the test channel for comparison, bit-by-bit with the actual address information transmitted by it.

Abstract: A telecommunication exchange system has a plurality of switch facilities over which signals are emitted on an average only during a part of their respective occupation. A signal current source for emission of the signals is provided having a call-handling capability limited by signal current load. A signalling system is provided for serving a distribution of the load and provides pulse sequences having respectively identical pulse spacings. Pulses of different pulse sequences simultaneously transmitted over different switch facilities have chronologically different phase relations and a chronological offset from switch facility to switch facility. The offset is such that the pulses of the different pulse sequences connect chronologically to one another with respect to pulse termination and pulse beginning. The switch facilities are allocated for receiving the pulse sequences from the signalling system to a respective one of the pulse sequences of a specific phase relation.

Abstract: Apparatus is described for monitoring the state, e.g., with regard to polarity, of signal lines in a telecommunication system. An input circuit, by means of high resistances relative to the line resistance, connects the lines to a differential amplifier having a predetermined threshold of response. A component of the amplifier output is applied to the input so as to have a polarity opposite to that of a bias voltage coupled to the amplifier. A capacitive protective circuit connected between the signal lines provides a time delay thereby protecting against interference pulses.