Aerospace Glossary Letters M - N


M

Magnetic Field – The region within which a body or current experiences magnetic forces.
Magnetic Flux – The rate of flow of magnetic energy across or through a surface (real or imaginary).
Magnetic Noise – Caused by change in current level, e.g. AC powerline (creates magnetic field around that cable) this magnetic field causes the magnetic noise.
Mastic – A meltable coating used on the inside of some shrink products which, when heated, flows to encapsulate the interstitial air voids.
MATV – Acronym for Master Antenna Television System - a combination of components providing multiple television receiver operations from one antenna or group of antennas; normally on a single building.
MCM – One thousand circular mils.
Meter – Unit of measurement, one meter equals 3.28 feet.
Mho – The unit of conductivity. The reciprocal of an ohm.
MHz – Megahertz (one million cycles per second). Formerly Mc.
Microwave – A short (usually less than 30 cm) electrical wave.
Mil – A unit used in measuring diameter of a wire or thickness of insulation over a conductor. One one-thousandth of an inch (.001).
Millimeter – One millimeter equals 0.03937 inches.
Mis-Match – A termination having a different impedance than that for which a circuit or cable is designed.
Modulation – The coding of information onto the carrier frequency. Modulation means include (among others) amplitude, frequency, or phase pulse many forms of on-off digital coding.
Modulus of Elasticity – The ratio of stress to strain in an elastic material.
Moisture Absorption – The amount of moisture, in percentage, that a material will absorb under specified conditions.
Moisture Resistance – The ability of a material to resist absorbing moisture from the air or when immersed in water.
Monomer – The basic chemical unit used in building a polymer.
MTW – An acronym for thermoplastic insulated Machine Tool Wire.
Multiplexing – Simultaneous transmission of two or more messages over the same cable medium. See TDM.
MUX – Multiplexer.
Mylar – DuPont trade name for a polyester material.

N

National Electrical Code (NEC) – A consensus standard published by the National Fire Protection 
Association (NFPA) and incorporated in OSHA regulations.
NBS – Abbreviation for National Bureau of Standards.
Nanosecond – One thousandth of one one millionth of a second (10-9 seconds).
NEMA – Abbreviation for National Electrical Manufactures Association.
NFPA – Abbreviation for National Fire Protection Association. That association responsible as the Administrative Sponsor of the National Electrical Code. Also identified as ""ANSI Standards Committee CI.
Non-Contaminating PVC – A polyvinylchloride formulation, which does not produce electrical contamination.
Nylon – A group of polyamide polymers which are used for wire and cable jacketing