Abstract: In a helical scanning type magnetic recording and/or reproducing apparatus for selecting one of output signals of two reproducing heads that are disposed at positions different by of 180° and transferring the selected output signal with a rotary transformer of one channel, a rotor side winding of a reproducing signal channel of a rotary transformer is divided into two portions. The divided portions are connected at two positions that are opposite to output terminals of head amplifiers that amplify output signals of reproducing heads and that have self short-circuit switches. Without use of extra wirings, the head amplifiers are directly connected to the rotary transformer. An output signal of the reproducing head is selected by short-circuiting a self short-circuit switch of a head amplifier corresponding to a head that does not reproduce a signal.

Abstract: A rotary head drum apparatus includes a stator drum. A rotary drum is provided with a plurality of magnetic heads and rotates the magnetic heads. The rotary drum is mounted for rotational movement with respect to the stator drum. A rotary transformer includes a stator-side rotary transformer provided on the stator drum and a rotating-side rotary transformer fixed to the rotary drum. The stator-side rotary transformer and the rotating-side rotary transformer are adapted to send and receive signals to each other. An adhesive providing gap is disposed between the rotating-side rotary transformer and the rotary drum for receiving an adhesive for bonding the rotating-side rotary transformer to the rotary drum. An adhesive splashing prevention part is provided on the rotating-side rotary transformer and receives adhesive splashing from the adhesive providing gap.

Abstract: According to the present invention, a hollowed portion is formed on a lower bonded surface of a rotary drum to which a rotation-side rotary transformer is bonded, and a hollowed portion is formed on an upper bonded surface of the fixed drum to which a fixation-side rotary transformer is bonded. Thus, excessive adhesive is absorbed by the hollowed portions and adhesive layers do not have uneven thicknesses, thereby securing surface runout accuracies of the rotary transformers. Further, since an adhesive is applied to the outer peripheral side of the hollowed portion of the rotary drum, the adhesive does not flow into ball bearings located on the inner peripheral side.

Abstract: In a helical scanning type magnetic recording and/or reproducing apparatus for selecting one of output signals of two reproducing heads that are disposed at positions different by of 180° and transferring the selected output signal with a rotary transformer of one channel, a rotor side winding of a reproducing signal channel of a rotary transformer is divided into two portions. The divided portions are connected at two positions that are opposite to output terminals of head amplifiers that amplify output signals of reproducing heads and that have self short-circuit switches. Without use of extra wirings, the head amplifiers are directly connected to the rotary transformer. An output signal of the reproducing head is selected by short-circuiting a self short-circuit switch of a head amplifier corresponding to a head that does not reproduce a signal.