Browse Prior Art Database

Magnetic Head Tester

IP.com Disclosure Number: IPCOM000077249D
Original Publication Date: 1972-Jun-01
Included in the Prior Art Database: 2005-Feb-25
Document File: 2 page(s) / 34K

Publishing Venue

IBM

Related People

Hyland, RN: AUTHOR [+2]

Abstract

A magnetic head may be analyzed by determining the phase difference between the voltage and current in its coil.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 2

Magnetic Head Tester

A magnetic head may be analyzed by determining the phase difference between the voltage and current in its coil.

A voltage signal A and the current signal B resulting from a sine wave applied to a head coil are both converted to square waves C and D. The pulses are compared by an inverter and positive AND circuit to yield a pulse E, having a width equal to the phase shift between the voltage and current signals. This pulse is then integrated to convert the phase shift to a DC value F.

The value may be scale factored so that 1 degree is equal to 0.1 volt. The constant-current source may limit the input impedance to between 100 omega and 7K omega in two ranges, 100 omega to 1K at 20ma and 500 omega to 7K at 2ma. Little would be required to operate the tester in different ranges.

1

Page 2 of 2

2

[This page contains 3 pictures or other non-text objects]