High-Frequency Recording Characteristics of Laminated Amorphous Film Heads

A Co-based laminated amorphous film head was tested in a rotary drum system at relative velocities from 5.8 m/s to 69.6 m/s. Sufficient contact was maintained between head and tape even at relative velocities as high as 69.6 m/s. Frequency loss in the head was caused by the playback output and recording sensitivity. The experimental data agreed well with the loss calculated from the frequency dependence of the initial permeability of the magnetic core using the magnetic circuit method. The frequency loss at 180 MHz/1.25 MHz was about 16 dB, and was independent of the magnetic field level.