Octave | A term that means to double the frequency |

Octave Bands | Frequency ranges in which the upper limit of each band is twice the lower limit. Octave bands are identified by their geometric mean frequency or center frequency |

Ohm | Unit of electrical resistance |

One-Third Octave Bands | Frequency ranges where each octave is divided into one-third octaves with the upper frequency limit being 2 1/3 (1.26) times the lower frequency. Identified by the geometric mean frequency of each band. |

Open | As in "open circuit" i.e: no current flow between two conducting surfaces |

| Maximum measurable ground isolation of an enclosure |

| Maximum resistance, usually beyond the range of the ohmmeter |

Parallel | The orientation for magnetic loop antennas per NSA-65-6. Oriented with the loops in a position parallel to the shield |

Passive Device | A component that does not provide rectification, amplification, or switching, but reacts to voltage and current |

Permeability | The ability of a material to carry magnetism, compared to air which has permeability of one. The capability of a material to be magnetized at a given rate. It is a non-linear property of both the magnetic flux density and the frequency of wave propagation |

Phase Lock | The control of an oscillator, so as to operate at a constant phase angle relative to a stable reference signal source. Primary use in analyzers is for frequency stability of oscillators |

Pink Noise | Broadband noise whose energy content is inversely proportional to frequency |

Planewave | A far field wave which exists at a distance greater than the wavelength divided by 2π from the source, where the impedance of the wave is nearly equal to the impedance of free space (377 ohms) |

Power | The time rate at which work is done. Power is expressed in watts |

Propagation | The travel of waves through or along a medium. A wave may propagate thru a wire, thru air or space, or thru a pipe or waveguide |

| A wave whose shape conveys some intelligence, message or effect |

| The transfer of energy by electromagnetic radiation at radio frequencies |