Getting to know the MD

Structure

The 2.5-inch MiniDisc (MD) is compact and easy to handle requiring less care as it is encased in a plastic cartridge that looks like a 3.5-inch diskette (see illustrations below).

Disc variation

MDs come in two types: pre-mastered (pre-recorded) and recordable (blank). Pre-mastered MDs cannot be recorded on or over like cassette tapes. To record, you must use a “recordable MD.”

Parts making up a MiniDisc

Plastic cartridge

Disc

Pre-mastered MDs

Pre-mastered MDs are recorded and played like regular CDs. A laser beam focus on the pits on the surface of the MD and reflects the information back to the lens in the recorder. The recorder then decodes the signals and plays them back as music.

Shutter

Recordable MDs

Recordable MDs, which use magneto- optical (MO) technology, can be recorded again and again. The laser inside the recorder applies heat to the MD, demagnetizing the magnetic layer of the MD. The recorder then applies a magnetic field to the layer. This magnetic field corresponds exactly to the audio signals generated by the connected source. (The north and south polarities equate to digital “1” and “0.”) The demagnetised MD adopts the polarity of the magnetic field, resulting in a recorded MD.

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Additional Information

 

59GB