Glossary U
UHF: Ultra High Frequency.

Ultrasonic: A frequency above the limits of the human ear - above 20kHz.

Unijunction Transistor: A trigger device that has an emitter lead (e) and two bases B1 and B2


Glossary V
Velocity: The time rate of change of displacement; dx/dt.

Volt: The (electrical) potential difference between two points in a circuit. One volt is the potential difference required to move one coulomb of charge between two points in a circuit while using one joule of energy. The fundamental unit is calculated as work done per unit charge-(V = W/Q).

Voltage: An electrical potential which can be measured in volts.

Voltmeter: An instrument used to measure voltage.

VOX: Voice operated Switch.


Glossary W
Waveform: A graphic representation of a voltage varying over time.

Waveform Point: A digital value that represents the voltage of a signal at a specific point in time. Waveform points are calculated from sample points and stored in memory.

Wheatstone Bridge: A network of four resistances, an emf source, and a galvanometer connected such that when the four resistances are matched, the galvanometer will show a zero deflection or "null" reading.

Window: In computer graphics, a defined area in a system not bounded by any limits; unlimited "space" in graphics.

Word: Number of bits treated as a single unit by the CPU. In an 16-bit machine, the word length is 16 bits; in a thirtytwo bit machine, it is 32 bits.

Working Standard: A standard of unit measurement calibrated from either a primary or secondary standard which is used to calibrate other devices or make comparison

Write: To record data in a storage device or on a data medium.