A fixed station operated by an educational organization and used primarily for the transmission of visual and aural instructional, cultural, and other types of educational material to one or more fixed receiving locations. [47 CFR
7
4. 901]

1. A radio-navigation system which provides aircraft with horizontal and vertical guidance just before and during landing and, at certain fixed points, indicates the distance to the reference point of landing. [NTIA] [RR]
2. A system of radio navigation intended to assist aircraft in landing which provides lateral and vertical guidance, which may include indications of distance from the optimum… (Read More →)

A system of vertical guidance embodied in the instrument landing system which indicates the vertical deviation of the aircraft from its optimum path of descent. [NTIA] [RR]

A system of horizontal guidance embodied in the instrument landing system which indicates the horizontal deviation of the aircraft from its optimum path of descent along the axis of the runway. [NTIA] [RR]

Telecommunications plant containing from one to six paired conductors, and possibly a shield. Wire may be found in either aerial or buried installations. [T1.316-1997]

An electronic circuit that consists of many individual circuit elements, such as transistors, diodes, resistors, capacitors, inductors, and other active and passive semiconductor devices, formed on a single chip of semiconducting material and mounted on a single piece of substrate material. Synonyms yychip, microcircuit. [From Weik '89]

A network that uses both digital transmission and digital switching.

A set of interconnected frames that is intentionally grounded via multiple connections to a ground reference. Multiple connections are intended to keep voltage drops (due to power faults in the ac or dc power systems or from lightning) to acceptable levels. The following are examples of an integrated ground plane: building steel, water pipes, ground rod systems, counterpoises, vertical and… (Read More →)

A circuit, or group of interconnected circuits, consisting of miniature solid-state optical components on semiconductor or dielectric substrates.
Note: IOC components include light sources, optical filters, photodetectors, and thin-film optical waveguides.

An integrated digital network in which the same time-division switches and digital transmission paths are used to establish connections for different services.
Note 1: ISDN services include telephone, data, electronic mail, and facsimile.
Note 2: The method used to accomplish a connection is often specified: for example, switched connection, nonswitched connection, exchange connection, ISDN connection.