3621153 is referenced by 8 patents and cites 3 patents.

A magnetic head having a plurality of read/write tracks, each track being formed of a single continuous lamina of high-permeability magnetic material which is wrapped around the edge of a support substrate and extends through an opening in the substrate. A coil encircles one leg of each of the lamina, the coils being alternately placed on opposite sides of the substrate to allow minimum space between the tracks. A magnetic gap extends less than the complete distance across each individual lamina parallel to the edge of the substrate. The electrical characteristics of each individual magnetic gap are monitored as the gap is cut. The cutting operation is terminated in accordance with the value of an electrical characteristic to obtain uniform gap characteristics for each of the gaps. The lateral position of the cut is adjusted in accordance with the value of an electrical characteristic to obtain longitudinal alignment of all of the gaps.

Title
Magnetic read/write head with partial gap and method of making
Application Number
04/887,147
Publication Number
3621153
Application Date
December 22, 1969
Publication Date
November 16, 1971
Inventor
John W Wenner
Agent
F A Sirr
Hanifin and Jancin
Assignee
International Business Machines Corporation Armonk NY
IPC
G11b 05/42
G11b 05/24
G11b 05/28
G11B 05/29
G11B 05/23
G11B 05/127
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