Circuit arrangement for a voice-controlled hands-free telephone facility

A voice-controlled hands-free facility contains a microphone, an internal and an external loudspeaker, and two series combinations of an input amplifier (EV), a variable attenuator (DR), and an output amplifier (AV), one for the send path and one for the receive path, and is controlled by a voice control unit (SS) connected to the output (E) of the input amplifier (EV), to the output (D) of the variable attenuator (DR), and, by a line (L), to an input of the variable attenuator (DR). To permit the hands-free facility to be switched from a single-part mode of operation to a two-part mode, the output (E) of the input amplifier (EV) in the send path and/or the receive path is connected to the output (A) of the output amplifiers (AV) through a bypass device (BP) and a switching unit (T).