electro-, electr-, electri-

A keying system that converts the Morse signals from a hand key into correctly proportioned and spaced dots and dashes.

Any spectrum produced by the absorption of electromagnetic radiation by ions, atoms, or molecules as a result of electron excitation.

1. A voltmeter consisting of a direct-current milliammeter calibrated in volts and connected to an amplifier-rectifier circuit.
2. A device that measures voltage in amplifier-rectifier circuits.

An instrument that determines the altitude of an object with respect to a fixed level.

The most common type is an aneroid barometer calibrated to show the drop in atmospheric pressure in terms of linear elevation as an airplane, balloon, or mountain climber rises.

It shows height above sea level, but not above such land features as hills, mountains, and valleys.

The radio altimeter, or terrain-clearance indicator, is an absolute altimeter which indicates the actual altitude over water or over terrain, regardless of how uneven it is.

It functions by first sending either continuous or pulse radio signals from a transmitter in an aircraft to the earth's surface.

1. The entire angular momentum including contributions from the spins of all the electrons in an atom.
2. The total angular momentum associated with the orbital motion of the spins of all the electrons of an atom.

A form of art which uses electronic materials; such as, moving and flashing light displays, as the artistic medium of presentations.

Simple electronic tags that can be turned on or off to indicate check-out or check-in status of products: When an item is purchased (or borrowed from a library), the electronic article surveillance is turned off.

When someone passes a gate, or door, of a place holding an item with an electronic article surveillance that hasn't been turned off, an alarm sounds.

A multicolor cathode-ray-tube display of attitude (angle of an aircraft) information, roll and pitch, showing the aircraft's position in relation to the instrument landing system or a very high-frequency omnirange station.

The term omnirange refers to a radio aid to navigation which provides a direct indication of the magnetic bearing (omnibearing) of that station from any direction.

An arrangement of gyroscopes, electronic amplifiers, and servomotors for detecting deviations in the flight of an aircraft, and applying the required corrections directly to its control cables.

1. A line on a radar screen that indicates the bearing of an airborne target.
2. On an airborne radar plan position indicator (PPI) a bright rotatable radial line used for determining the bearing of an aircraft.

1. A micro-balance in which the sample weight is obtained automatically, based on the force produced by current in a coil in a magnetic field.
2. A weighing balance which uses forces produced by known currents to balance unknown currents and, so make unknown weights come to within parts of a microgram.

A spectrum band composed of molecules which is usually found in the visible or the ultraviolet because of the electron transition taking place with the molecule.

1. A spectrum characteristic of molecules that consists of bands of spectral lines corresponding to electron transitions accompanied by vibrational or rotational transitions.
2. Bands of spectral lines connected with a change of electronic state of a molecule.

Each band is corresponding to vibrational energies in the initial and final conditions and each band consists of numerous rotational lines.

1. A narrow stream of electrons moving in the same direction under the influence of an electric or magnetic field.
2. A stream of electrons, emitted by a single source, which move in the same direction, and at the same speed.
3. A stream of electrons which can "write" on phosphor surfaces; such as, a CRT screen expose photoresistent-coated semiconductor wafers by direct writing or exposure through a mask, or magnify objects by passing through magnetic "lenses".

It can also be a cutting tool.

A cathode-ray tube, or CRT, produces images when its phosphorescent surface is struck by electron beams.

1. A line on a radar screen which indicates the bearing of a marine target.
2. A reference to a marine radar set, the bright rotatable radial line on the plan position indicator that is used for the determination of bearing or the calculation of a direction or a geographic position.