Title :
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
fDate :
9/1/1997 12:00:00 AM
Abstract :
The system described measures the magnetic laydown density (Mr 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;
Journal_Title :
Magnetics, IEEE Transactions on
