A head drum assembly, for use in a video cassette recorder, comprises a rotary drum provided with a circumferential side wall and at least one opening provided thereon, a pair of heads each of which is provided with a head chip and a head base, a guide member for guiding the head base in a direction that is substantially parallel to the rotating shaft, and an electromagnet for moving the head in the direction parallel to the rotating shaft while the head chip is in contact with the magnetic tape. The rotary drum is held rotatable by a bracket. The heads are disposed 180.degree. from each other on an inner bottom surface of the rotary drum, the head chip coming in contact with a magnetic tape partially wrapped around the rotary drum through the opening. The guide member is secured on the inner bottom surface of the rotary drum, guiding the head base in the direction parallel to the axis of the rotary drum. The electromagnet is curved along a path of rotation of the head base and is held stationary immediately above the guide member by a holder secured to the bracket, moving the head in the direction parallel to the axis of the rotary drum to allow the head chip to dynamically follow the track recorded on the magnetic tape.

A mount for electrical leads to a vibration-type sensor and/or for coils on a vibration-type sensor. The mount includes at least one resilient first arm attached to a first sensing tube of the sensor and at least one resilient arm attached to a second sensing tube of the sensor. The two sensing tubes, which are caused to vibrate during operation of the sensor, form a double-tube arrangement having a longitudinal gravity line, which lies in an imaginary central plane extending between the two, preferably parallel, sensing, tubes. The two arms of the mount are essentially rigidly connected to one another at a connecting location remote from the two sensing tubes, and the mount exhibits a first eigenmode of predeterminable mechanical resonance frequency, f.sub.1, at which the first arm attached to the first sensing tube and the second arm attached to the second sensing tube oscillate pendularly essentially perpendicular to the central plane of the double-tube arrangement. The mount exhibits a second eigenmode of predeterminable mechanical resonance frequency, f.sub.2, at which the first arm attached to the first sensing tube and the second arm attached to the second sensing tube oscillate pendularly essentially parallel to the central plane of the double-tube arrangement, and the resonance frequency, f.sub.1, of the first eigenmode is different from the resonance frequency, f.sub.2, of the second eigenmode.

A rotating magnetic head for a magnetic recording reproduction system. The rotating magnetic head detects the position of the rotating head placed on the periphery of a rotating drum, and perform servo control of the position of the movable head. The detection of the position of the rotating head is realized by an optical, non-contact mechanism or by detecting the difference of the track scanned by fixed heads. The former requires more than one movable heads and the latter requires a fixed head.

A mount for electrical leads to a vibration-type sensor and/or for coils on a vibration-type sensor. The mount includes at least one resilient first arm attached to a first sensing tube of the sensor and at least one resilient arm attached to a second sensing tube of the sensor. The two sensing tubes, which are caused to vibrate during operation of the sensor, form a double-tube arrangement having a longitudinal gravity line, which lies in an imaginary central plane extending between the two, preferably parallel, sensing tubes. The mount exhibits a first eigenmode of predeterminable mechanical resonance frequency, at which the first arm and the second arm oscillate pendularly essentially perpendicular to the central plane of the double-tube arrangement. The mount exhibits a second eigenmode of predeterminable mechanical resonance frequency, at which the first arm and the second arm oscillate pendularly essentially parallel to the central plane of the double-tube arrangement, and the resonance frequency, of the first eigenmode is different from the resonance frequency, of the second eigenmode.

A rotating drum device, of a tape that a magnetic head scans recording tracks which are formed obliquely with respect to a travelling direction of a magnetic tape at any speed of the magnetic tape, comprises a driving part attached to a rotating drum, a supporting member supporting a magnetic head, a coil mounted on the supporting member and a magnetic unit. A control electric current is supplied to the coil depending on the travelling speed of the magnetic tape to produce a magnetic force, whereby the magnetic head is vertically moved along the axis of rotation of the rotating drum.