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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.
Magnetic tape reader