Abstract: A device for detecting the position of a recording/read head (20) for use with a magnetic tape, the head being fixed to the free end of an elongate support (14) fixed to a component (5) which is mounted to rotate in a slot (4) provided in an equatorial plane of a cylindrical drum (1) on whose outside surface the recording tape is wound helically. Said support is capable of bending in a direction (f) which is transverse to the direction of relative head-to-head tape displacement. The device is characterized in that it includes a position sensor comprising a variable electrical capacitance including a fixed plate (32) fixed to the drum (1) of the moving plate (24) fixed to said head support, together with measurement means (33, 34, 35.sub.i) which are sensitive to said capacitance and are suitable for providing a signal representative of the position of the head support (14) and thus of the head (20).