NCJ Number
18038
Date Published
1972
Length
34 pages
Annotation
DISCUSSION OF RESULTS AND IMPLICATIONS OF EXPERIMENTS PERFORMED WITH DIFFERENT TYPES OF MAGNETS TO DETERMINE THEIR EFFECTS ON THE INFORMATION STORED ON MAGNETIC STORAGE MEDIA.
Abstract
THIS REPORT DEALS PRIMARILY WITH THE EFFECTS OF PERMANENT MAGNETS ON THE RECORDED INFORMATION ON MAGNETIC COMPUTER TAPES. THE RESULTS OF THIS STUDY ARE DIRECTLY APPLICABLE TO THE OTHER MAGNETIC SURFACE DEVICES SUCH AS DISKS AND DRUMS. THE STUDY ALSO DISCUSSES BOTH THE CAPABILITIES AND LIMITATIONS OF THE PERMANENT MAGNET AND THE ELECTROMAGNET AS DESTRUCTIVE DEVICES. SECTION TWO OF THIS REPORT PRESENTS A NUMBER OF GUIDELINES TO BE USED IN COMPUTER INSTALLATIONS FOR PROTECTING THEIR MAGNETICALLY RECORDED DATA FROM INTENTIONAL OR ACCIDENTAL DAMAGE. SECTION THREE USES A QUESTION-AND-ANSWER FORMAT TO DISCUSS TOPICS THAT ARE OF INTEREST TO THE MANAGERS OF COMPUTER INSTALLATIONS. THESE DEAL MAINLY WITH THE EFFECTS OF MAGNETIC FIELDS ON RECORDED MAGNETIC COMPUTER TAPES. SECTION FOUR DESCRIBES THE EXPERIMENTS THAT WERE PERFORMED IN ORDER TO ANSWER SOME OF THE QUESTIONS THAT WERE POSED IN SECTION THREE. SECTION FIVE PRESENTS ADDITIONAL TEST RESULTS AND COMMENTS CONCERNING THE EFFECTS OF OTHER POSSIBLE SOURCES OF DAMAGE TO MAGNETIC MEDIA. (AUTHOR ABSTRACT)