Low concentration magnetic media tester

Author

Chamberlain, Fred R. ; Jeffers, Fred J. ; Smith, Neil ; James, Robert O.

Author_Institution

Eastman Kodak Co., San Diego, CA, USA

Volume

33

Issue

5

fYear

1997

fDate

9/1/1997 12:00:00 AM

Firstpage

4014

Lastpage

4016

Abstract

The system described measures the magnetic laydown density (M_r thickness product) of low concentration magnetic coatings, such as the coating on Advanced Photo System photographic film. The measurement is accurate for coatings having a magnetic coverage as small as 0.1 memu/cm². The system consists of a roller recorder, a flux guided paired magnetoresistive (FGPMR) head mounted in a card swipe reader, an amplifier channel, and a digital scope. Laydown density is measured by affixing a small coating sample to a plastic card, roller recording it to produce isolated transitions, and swiping it through the reader. The RMS signal output is linearly proportional to the laydown density

Keywords

magnetic recording; magnetic variables measurement; test equipment; Advanced Photo System photographic film; amplifier channel; digital scope; flux guided paired magnetoresistive head; low concentration magnetic coating; magnetic laydown density measurement; magnetic recording medium tester; plastic card swipe reader; roller recorder; Insulation; Magnetic fields; Magnetic flux; Magnetic heads; Magnetic separation; Magnets; Saturation magnetization; Temperature sensors; Testing; Voltage;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.619647

Filename

619647