The Effect of Conducting Gap Spacers on the Impedance of Magnetic Heads
The impedance of magnetic recording heads at high frequencies is reduced by making the gap spacer of conducting material, because eddy currents in this conductor lower the permeance of the gap region. The traditional formulas for the complex permeability versus frequency of a conducting lamination (as used in transformer design) apply within the gap area. The formulas involve spacer initial permeability, resistivity, and the gap depth which corresponds to the usually used lamination thickness. Measurements of impedance versus frequency of a large -model- head verify the theory.
Click to purchase paper or login as an AES member. If your company or school subscribes to the E-Library then switch to the institutional version. If you are not an AES member and would like to subscribe to the E-Library then Join the AES!
This paper costs $20 for non-members, $5 for AES members and is free for E-Library subscribers.