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Magnetic tape reader

A magnetic tape reader takes the information from a magnetic tape and converts it into an electrical signal (which, in a cassette player, is in turn sent to a speaker to be converted into sound). The basic set-up of the tape reader is similar to that of the tape recorder of Fig. 9.15. A magnetic tape, in which information is encoded in terms of a particular orientation of the magnetic fields of the atoms, is passed underneath the reader, which causes a magnetic field to be induced through the plane of the wire loops. Different orientations of the atoms means that the magnetic field through the wire loops will be changing, which subsequently induces a current. This electrical signal is then passed on to some other device, like a speaker, for further processing.