Switching device for transmitting telecommunication signals

A switching device for transmitting telecommunication signals between an exchange of a telephone network and at least one subscriber device with which metering pulses in addition to voice signals are transmitted by the exchange, in which the exchange and the subscriber device are each allocated system units between which the voice signals are transmitted as digital signals via a two-wire line, and in which the system units, in addition to analog/digital converters, have a hybrid switching unit with a transformer for connecting two-wire line to a four-wire line, and in which the two-wire line containing the primary winding of the transformer is connected to the exchange, while the two wire line leading to the subscriber device is connected to a four-wire line, consisting of a transmitting branch and a receiving branch, and containing the secondary winding of the transformer, characterized in that

• the two-wire line contains a parallel resonant circuit (P), which consists of an inductance (3) and a capacitor (4),
• a passive filter (8) and an active filter (9) are connected in series in the receiving branch of the hybrid switching unit;
• the passive filter (8) is tuned for attenuating the frequency of the metering pulse, and
• the active filter (9) is tuned to the passive filter (8), so as to compensate for a decrease in the level of the voice signals caused by the passive filter (8), by generating a corresponding increase in the voice signal.