The invention relates to an adapter device (10, 110, 210) for positioning at least one conductor (68), such as a conductor pair, for example, of a cable (70) to be measured, which adapter device comprises a receiving device (12) and a holding clamp (14) which can be attached to the receiving device (12). Attaching the holding clamp (14) to the receiving device (12) fixes the holding clamp (14) in position and alignment relative to the receiving device (12). The holding clamp (14) is designed to receive and clamp the at least one conductor (68) of the cable (70) to be measured in sections in order to fix said cable in the position and alignment thereof relative to the holding clamp (14), such that an end section of the at least one conductor (68) extends beyond the holding clamp (14).