| Term |
Meaning |
| AC: |
Alternating Current. Changes (or alternates) in magnitude and direction at regular intervals. |
| ADSL: |
Asymmetric Digital Subscriber Line. Technology that transmits digital information at a high bandwidth on existing phone lines, delivering broadband internet access to homes and businesses. |
| Aerial: |
A device for radiating and receiving radio waves. |
| Alkaline: |
Used to describe a type of high capacity primary (single-use) battery. |
| AMD: |
Advanced Micro Devices. AMD is a leading manufacturer of CPUs. |
| Amp: |
Abbreviation for ampere (see Current) and abbreviation for amplifier. |
| Amplifier: |
A device that increases the level of an electrical signal. |
| ANSI: |
American National Standards Institute. The organisation responsible for administrating and coordinating the voluntary standardisation system for the private sector in the United States. |
| Antenna: |
Another name for aerial. |
| ASCII: |
American Standard Code for Information Interchange. A standard code used to represent English characters in computers. |
| Athlon: |
Brand name applied to a series of CPUs designed and manufactured by AMD. Athlon 64 is the eighth-generation processor featuring AMD64 technology |
| ATX: |
PSU Power Supply Unit for the modern layout of computer motherboards. |
| AV: |
Audio Video. A generic term for equipment designed to handle audio and video. |
| Axial: |
A horizontal pin arrangement - pins are on either end of a component |
| Ba15d: |
Bayonet, 15mm, double contact. Bulb base also known as SBC. |
| Ba15s: |
Bayonet, 15mm, single contact. Bulb base also known as SCC. |
| Ba22d: |
Bayonet, 22mm, double contact. Bulb base also known as BC. |
| Ba9s: |
Bayonet, 9mm, single contact. Bulb base also known as MBC. |
| Bass/mid: |
A loudspeaker that handles the lowest part in the musical range. |
| Baud Rate: |
A technical term associated with modems, GPS devices and other items of technology. It is also known as symbol rate or modulation rate. The term roughly indicates the speed that data is transmitted. It is a derived value based on the number of symbols transmitted per second. |
| BC: |
Bayonet Cap. Bulb base also known as Ba22d |
| BIOS: |
Basic Input/Output System. Part of an operating system that handles communications between the computer and its peripherals. |
| Bit: |
Binary digit. The smallest unit of information on a computer, usually designated 0 or 1 (representing on/off states) |
| Bluetooth: |
A short range (10m) wireless protocol for data exchange. Commonly used to connect wireless earpieces to mobile phones and PDAs to laptops, etc.Operates at 2.45GHz |
| BNC: |
A Connector used on video, RF and networking equipment providing a secure bayonet attachment. |
| Bus: |
The pathways by which electronic data moves between parts of a computer. Different types of buses move the data in different size packages. |
| Byte: |
Unit of memory storage equivalent to 8 bits. Computer memory and storage is usually measured in kilobytes (kB = 1024 bytes), megabytes
MB = 1024 kilobytes), and gigabytes (GB = 1024 megabytes)
|
| Cache: |
Discrete computer memory used to store frequently accessed information from the disk drive in order to speed up disk access. |
| Capacitance: |
Measured in farads (F). A measurement of the ability to store electricity while under load. |
| Capacitor: |
Passive component that stores an electrical charge. |
| Carbon Resistor: |
Used in low cost applications due to its inferior tolerance and temp stability. |
| Card Reader: |
A device used with a PC to read data from Flash Memory cards (such as CF, SD, MMC, MS, etc). |
| CCTV: |
Closed Circuit Television. A video system used for specific purposes such as security, medical and educational. |
| CD: |
Compact Disc. An optical media format, based on a 120mm diameter plastic disc, with a 650MB capacity used to store audio, video or computer data. |
| CD-R: |
Compact Disc - Recordable. A recordable CD that can be written to once. |
| CD-ROM: |
Compact Disc - Read Only Memory. A compact disc used for storing computer data, programs, images, music, etc. |
| CD-ROM drive: |
A device that retrieves data from a CD-ROM disc. It differs from a standard audio CD player by the incorporation of additional error-correction circuitry. Audio CDs can also be played on CD-ROM drives. |
| CD-RW: |
Compact Disc - ReWritable. A recordable CD that can be re-written to and erased multiple times. |
| CF: |
see "compact flash" |
| Chip: |
Another name for an IC. Cased in a plastic or ceramic carrier device with pins for making electrical connections. |
| Chipset: |
A single chip or set of chips that integrate into the clock generator, bus controller, system timer, interrupt controller, DMA controller and CMOS RAM/clock and keyboard controller on a motherboard. |
| Coax: |
Short for coaxial, an electrical cable with a central conductor and an outer screening layer separated by an insulating layer. Typically used for RF connections. |
| Compact Flash: |
One of several versions of small memory storage cards that uses flash memory to store information. Typically used in portable devices such as cameras and MP3 players. |
| Component Video: |
Used for higher quality video signals. Like S-Video the luminance (Y) is sent as one signal,but the colour is further split into component parts. This is variously described as YUV, YCbCr or YPbPr (there is technically some difference between these but manufacturers seem to use these synonymously). Typically the connectors are three phono sockets coloured red, green and blue. This leads to component video sometimes, erroneously, being referred to as RGB. Common on video projectors, plasma screens and higher-end DVD players. |
| Composite Video: |
A video signal that combines all the necessary component signals. The TV has to separate them with filters, with a subsequent loss in quality. This is the signal used by most standard SCART connectors and also found on the yellow phono sockets found on some equipment, such as camcorders, variously labelled video, composite or CVBS. |
| Cooling Fan: |
A fan found within a computer that prevents the parts inside the computer from overheating |
| Coulomb: |
Standard unit of electrical charge. |
| CPU: |
Central Processing Unit. Computer’s microprocessor chip - the brains of the outfit. A programmable logic device that performs all the instruction, logic and mathematical processing in a computer. |
| Crimp: |
This is a process of inserting a conductor in to the tubular portion of a connector. By using a special tool to squeeze the tube until it grips the conductor and forms a strong mechanical and electrical connection. |
| Crystal: |
A device which has a natural resonance, used in oscillators and filter circuits. |
| Current: |
Measured in amperes (A). The rate at which electrical charge moves, 1A = 1 coulomb per second. |
| CVBS: |
See "Composite Video". |
| DAB: |
Digital Audio Broadcasting. Over-the-air broadcast digital radio using compressed digital data for transmission. |
| Darlington: |
A transistor pair configuration to achieve large hfes |
| DAT: |
Digital Audio Tape. A digital recording format that allows music to be digitally stored onto magnetic cassette tape. |
| DC: |
Direct Current. Flows consistently in one direction only. |
| DDR: |
Double Data Rate. An advanced version of SDRAM. DDR-SDRAM can transfer data twice as fast as regular SDRAM chips. |
| DECT: |
Digital Enhanced Cordless Telecommunications. A digital cordless telephone standard with improved clarity and range and enhanced features compared to analogue cordless. |
| Device Driver: |
A program that provides an interface for a particular piece of hardware to an operating system or other standard software. |
| Diac: |
A bi-directional diode used for triggering triacs. |
| Dielectric: |
Insulating layer of a capacitor. |
| DIMM: |
Dual In-line Memory Module. A small circuit board that holds memory chips. A single in-line memory module (SIMM) has a 32-bit path to the memory chips whereas a DIMM has a 64-bit path. |
| DIN: |
Deutsche Industrie Norm. German standard, used to describe a range of multipin AV connectors. |
| Diode: |
Active component that conducts current in only one direction. |
| DMX: |
Digital MultipleX. A protocol used to control lighting effects and dimmers in theatres, etc. |
| DPDT: |
Double Pole, Double Throw (of switches or relays). |
| DPST: |
Double Pole, Single Throw (of switches or relays). |
| DRAM: |
Dynamic Random Access Memory. Type of computer memory, DRAM is relatively inexpensive because it only requires one transistor and a capacitor to represent each bit. DRAM is volatile, meaning it loses data when power is removed. |
| Driver: |
A program that provides an interface for a particular piece of hardware to an operating system or other standard software. |
| D-Sub: |
Multi-pin connectors that are commonly used for computer connectivity. |
| DV: |
Digital Video. A format for storing digital audio and video. In its smaller tape form factor, Mini DV has become the standard for consumer and semi-professional video production. Data is transferred using the IEEE-1394 (Firewire) connection. |
| DVD: |
Digital Versatile Disc (also known as Digital Video Disc). Similar to a CD but with much higher storage capacity (typically from 4.5GB to 17GB for doublesided discs). |
| DVD+R: |
Digital Versatile Disc - Recordable, “DVD plus R”. One of two competing writeonce recordable DVD formats. |
| DVD+RW: |
Digital Versatile Disc - ReWritable, “DVD plus RW”. One of two competing re-recordable and erasable DVD formats. |
| DVD-R: |
Digital Versatile Disc - Recordable, “DVD minus R”. One of two competing write-once recordable DVD formats. |
| DVD-RAM: |
Digital Versatile Disc - Random Access Memory. A re-writable DVD format that is usually housed in a caddy so is not compatible with most home DVD video players. |
| DVD-RW: |
Digital Versatile Disc - ReWritable, “DVD minus RW”. One of two competing re-recordable and erasable DVD formats. |
| D-VHS: |
Digital - Video Home System. A VCR format that is capable of recording HDTV programmes at their full resolution. |
| DVI: |
Digital Visual Interface. Connection standard developed for connecting digital video signals between computers and digital monitors such as flat panels and projectors. |
| E10: |
ES, 10mm. Bulb base also known as MES. |
| E14: |
ES, 14mm. Bulb base also known as SES. |
| E27: |
ES, 27mm. Bulb base also known as ES. |
| E40: |
ES, 40mm. Bulb base also known as GES. |
| E5: |
ES, 5mm. Bulb base also known as LES. |
| Electrolytic Capacitor: |
High capacity/space ratio, commonly used as smoothing capacitors in PSUs. |
| Embedded Memory: |
Embedded memory is built directly into a device and is a non-removable form of digital storage. |
| ES: |
Edison Screw. Bulb base also known as E27 |
| Expansion card: |
An integrated circuit card that plugs into an expansion slot on a motherboard to provide access to additional peripherals. |
| Ferrite: |
A powdered, compressed and sintered magnetic material used to increase impedance and reduce high frequency interference. |
| Firewire: |
Apple’s propriety name for its IEEE-1394 compliant bus. |
| Flash Memory: |
Non-volatile storage device (i.e. it retains stored data even when unplugged). |
| Floppy Disk: |
A portable data storage medium. Most common floppy disks are 1.44MB in size. |
| Fluorescent: |
The quality of having the ability to emit light when struck by electrons or another form of radiation. |
| FME: |
RF connector used for mobile antenna applications featuring a miniature screw coupling coax connector with a 50Ω impedance. |
| Forward Current: |
The current required by an LED to make it shine at its optimum brightness. |
| Forward Voltage: |
The voltage required across the LED to make it illuminate at the maximum brightness. |
| Frequency: |
Measured in hertz (Hz). The number of cycles of a periodic event within a fixed time, 1 Hz = 1 cycle per second. |
| Fuse: |
A safety protection component that breaks the circuit when its rated current is exceeded. Made with a metal wire that melts when the current gets too high. |
| GB: |
Gigabyte - see "byte" |
| GES: |
Goliath Edison Screw. Bulb base also known as E40. |
| giga (G): |
Prefix indicating a power of 10^9 or 1,000,000,000. In binary (computer use) indicates 2^30 or 1,073,741,824 gigabyte See Byte. |
| GPS: |
Global Positioning System. Worldwide radio navigation system, based on a string of US military satellites, also referred to as satellite navigation (Sat Nav). |
| Halogen: |
A type of incandescent lamp with higher energy-efficiency and bright white light. |
| Hard disk/drive: |
A high capacity re-writable storage unit, characterised by a normally nonremovable rigid substrate medium. Used for long-term storage of software, files and documents. |
| HDMI: |
High Definition Multimedia Interface. A digital AV standard that is being adopted on high definition home entertainment equipment and is backwardly compatible with DVI video signals and has the advantage of also connecting digital audio. |
| HFE: |
In a transistor, the current gain when placed into a common-emitter circuit. |
| Hi-fi: |
High Fidelity. Definition for high quality sound systems. |
| Hub: |
A networking device which has sockets for multiple cables (from PCs, servers, etc.), which retransmits the signals from one device to all other devices on the hub. |
| Hygrometer: |
An instrument used for measuring relative humidity in the atmosphere. |
| i.Link: |
Sony’s propriety name for its IEEE-1394 compliant bus. |
| Ibe: |
In a transistor, the maximum base to emitter current. |
| IC: |
Integrated Circuit. A circuit made from transistors and passive components on a common substrate. |
| Ice: |
In a transistor, the maximum collector to emitter current. |
| IDC: |
Insulation Displacement Connector. High density header connectors used on ribbon cables for internal drives. |
| IEEE-1394: |
IEEE-1394 is the standard for a high performance serial bus, also called Firewire by Apple and i.Link by Sony. It is similar to USB. It provides a single plug-and-socket connection on which up to 63 devices can be attached with max data transfer speeds up to 400 Mbps. Standard connection for DV camcorders. |
| Impedance: |
Measured in ohms (Ω). The total opposition offered to the flow of AC at a particular frequency. It is a combination of resistance and reactance. |
| Inductance: |
Measured in henries (H). The property of a circuit to oppose a change in current because of the opposing voltage induced by the moving magnetic field created by the original current. |
| Inductor: |
Passive component, usually a coil, that stores energy as a magnetic field and introduces impedance. |
| Intel: |
Intel is a leading manufacturer of CPUs. |
| Intercom: |
A communication system linking different areas. |
| ISA: |
Industry Standard Architecture. A 16 bit computer bus architecture, ISA slots can still be found on some PCs. |
| ISDN: |
Integrated Services Digital Network. A system of digital telephone connections. Multiple digital channels can be operated simultaneously through a single interface. |
| kB: |
Kilobyte - see "byte" |
| Keyboard: |
An input device that has various keys that allows the user to input data to a workstation. |
| Kilo: |
(k) Prefix indicating a power of 10^3 or 1,000. In binary (computer use) indicates 2^10 or 1,024 kilobyte See Byte |
| KVM: |
Keyboard-Video-Mouse. A switch that allows multiple computers to share one keyboard, one monitor, and one mouse. |
| Laptop: |
A portable computer. Sometimes referred to as a notebook. |
| Laser: |
Light Amplification by Stimulated Emission of Radiation. Coherent light that does not diverge over long distances. |
| LCD: |
Liquid Crystal Display. Screen used to display text/graphics based on a technology called liquid crystal, where minute currents change the reflectiveness or transparency of the screen. Used to create flat screen monitors and TVs. |
| LDR: |
Light Dependant Resistor. A component whose resistance varies with the ambient light level. |
| LED: |
Light Emitting Diode. Active component that lights up when a current is passed through it. |
| LES: |
Lilliput Edison Screw. Bulb base also known as E5. |
| Lithium-ion: |
Also commonly known as lithium polymer batteries(abbreviated to Li-poly, Li-Pol, LiPo, LIP, PLI or LiP), lithium-ion batteries are rechargeable batteries. They are normally batteries composed of several identicalsecondary cells in parallel addition to increase the discharge current capability. |
| Magnifier: |
An optical device used to observe very small details. |
| MB: |
Megabyte - see "byte" |
| MBC: |
Miniature BC. Bulb base also known as Ba9s. |
| MCC: |
Miniature Centre Contact. Bulb base also known as Ba9s. |
| MD: |
See "minidisc" |
| mega (M): |
Prefix indicating a power of 10^6 or 1,000,000. In binary (computer use) indicates 2^20 or 1, 048, 576 megabyte See Byte. |
| Memory Stick: |
Sony’s version of a small memory storage card that uses flash memory to store information. Typically used in portable devices such as cameras and MP3 players. |
| MES: |
Miniature Edison Screw. Bulb base also known as E10. |
| Metal Film Resistor: |
Used in applications where good tolerance and temp stability is desired. |
| micro (μ): |
Prefix indicating a power of 10^-6. |
| Micro MV: |
Small digital video cassette format devised by Sony. |
| Microcassette: |
A smaller format of the compact audio cassette. |
| MIDI: |
Musical Instrument Digital Interface. A system for connecting synthesisers and other studio equipment that usually employs 5-pin DIN connectors. |
| milli (m): |
Prefix indicating a power of 10^-3. |
| Mini CD: |
A small version of the CD with an 80mm diameter, with a 210MB capacity. |
| Mini DV: |
A video cassette designed for use in Mini DV digital camcorders (see DV). |
| MiniDisc: |
A trademarked recordable optical media by Sony, consisting of a small optical disc encased within a protective 72mm by 68mm case in order to protect the disc. |
| MMC: |
See MultiMedia Card. |
| Modem: |
Modulator-Demodulator device. Allows computers to transmit information to one another via audio signals down a telephone line. |
| Module: |
A separate and distinct unit of hardware or software that is used as a component in a system. |
| Motherboard: |
The foundation of a PC - the large PCB that handles system resources as well as having a number of sockets and slots for the CPU, memory, graphics card, etc. Some motherboards feature integrated peripherals such as modems, sound, graphics and network cards. |
| Mouse: |
A computer input device which often consists of a roller ball and a tracking mechanism, though optical mice with no moving parts are also very popular. |
| MP3: |
MPEG-1 Audio Layer-3. Standard format for compressing music and audio into a very small file. |
| MS: |
See "Memory Stick" |
| MultiMedia Card: |
One of several versions of small memory storage cards that uses flash memory to store information. Typically used in portable devices such as cameras and MP3 players. |
| Multimeter: |
An electronic measuring instrument. Used to measure volts, ohms, amperes, etc. |
| N/C: |
Normally Closed (of switch or relay contacts). |
| N/O: |
Normally Open (of switch or relay contacts). |
| nano (n): |
Prefix indicating a power of 10^-9. |
| NMEA: |
An electrical and data specification for communication between electronic devices such as GPS receivers, autopilot systems and many other types of instruments. It has been defined by, and is controlled by, the U.S.-based National Marine Electronics Association (hence the name). |
| Operating System: |
Collection of programs for operating the computer, such as Windows, MacOS, Linux, etc. |
| Optoelectronics: |
Products that combine electronics with optical sensitivity. |
| Oscilloscopes: |
An electronic measuring instrument. It creates a visible two-dimensional graph of one or more electrical potential differences. |
| PCB: |
Printed Circuit Board. Usually made from fibreglass with copper tracks, the board acts as a base for components to be mounted and connected via the copper tracks. |
| PCI: |
Peripheral Component Interconnect. A standard bus specification that bypasses the standard ISA I/O bus and uses the system bus to increase the bus clock speed and take full advantage of the CPU’s data path. You can connect a PCI card to the motherboard for a sound card, network card, graphics card and internal modems. |
| PDA: |
Personal Digital Assistant. A handheld computer but not as powerful as a laptop or desktop computer. |
| Pentium: |
Brand name applied to a series of CPUs designed and manufactured by Intel. |
| Peripheral: |
Equipment that is used in computer systems. An attachment to a computer. |
| Phono: |
Connector Standard connector used for both audio and video. Known as RCA in the US. |
| pico (p): |
Prefix indicating a power of 10^-12. |
| Plasma: |
A low density gas in which the individual atoms are charged. Recently used to create large-screen TVs. |
| PMPO: |
Peak Music Power Output - music power average over a finite time. |
| PMR: |
Private Mobile Radio. License-free radio band used for 2-way walkie-talkies. |
| Polypropylene Capacitor: |
High voltage, excellent stability and tolerance. |
| Potentiometer: |
A variable resistor. |
| Power: |
Measured in watts (W). Product of voltage and current ( V x I ). |
| Printer: |
Visual recording device, most commonly on paper. |
| Projector: |
A device that integrates a light source, optics system, electronics and display(s) for the purpose of projecting an image onto a wall. Used to project TV and video on to a big screen. |
| PSU: |
Power Supply Unit. Typically converts mains AC into low voltage DC. |
| Radial: |
Vertical pin arrangement - pins are on one end of a component. |
| RAM: |
Random Access Memory. RAM is the most common type of memory found in computers and other devices, such as printers. |
| Reactance: |
Measured in ohms (Ω). The opposition to the flow of AC caused by either capacitance or inductance. |
| Relay: |
An electrically operated switch. |
| Resistance: |
Measured in ohms (Ω). A measure of the opposition to the flow of current. |
| Resistor: |
Passive component with electrical resistance to current flow. |
| Resonator: |
Device that has a natural resonance, used in oscillators and filter circuits. |
| RF: |
Radio Frequency. Electromagnetic waves that can carry data signals that are superimposed for transmission of audio, video, etc. |
| RGB: |
High quality analogue video signals. True RGB sends the three colours separately and requires a separate synchronisation signal. All these are available in an RGB configured SCART (see SCART information panel), as found on many TVs, Sattelite and cable boxes. |
| RJ45: |
Registered Jack-45 is an eight-wire connector. Used to connect computers onto local area networks. |
| RMS: |
Root Mean Squared. An AC voltage that equals the DC voltage that will do the same work. For a sinusoidal current it is 0.707 x peak voltage. |
| SBC: |
Small BC. Bulb base also known as Ba15d |
| Scanner: |
A device that reads images into a computer. The image is translated into computer data. Also radio: a device that monitors a range of radio frequencies. |
| SCART: |
A 21-pin audio/video connector used on TVs, VCRs, DVD players, etc. Named after the Syndicat des Constructeurs d’Appareils Radiorecepteurs et Televiseurs and also known as Peritel. |
| SCC: |
Small Centre Contact. Bulb base also known as Ba15s |
| SCR: |
Silicon-Controlled Rectifier. A three-terminal active component that acts as a gated diode. Triggering the gate turns on the device, allowing current to flow. |
| SCSI: |
Small Computer Systems Interface. A system that allows multiple devices to be connected to a computer. |
| SD: |
See "Secure Digital Card". |
| Secure Digital Card: |
One of several versions of small memory storage cards that uses flash memory to store information. Typically used in portable devices such as cameras and MP3 players. |
| Semiconductor: |
An element that is intermediate in electrical conductivity between conductors and insulators. Doped silicon is the most commonly used and is the basis of modern electronics. |
| Series Resistor: |
The resistor required to limit the forward current and voltage so the LED will not overheat. It may be calculated using: R = (V.supply-V.forward) / I.forward. Then match this up with a resistor equal or greater than this value. |
| SES: |
Small Edison Screw. Bulb base also known as E14. |
| SM: |
See "SmartMedia". |
| SmartMedia: |
One of several versions of small memory storage cards that uses flash memory to store information. Typically used in portable devices such as cameras and MP3 players. |
| SMPS: |
Switch Mode Power Supply. Instead of a transformer, a switching circuit is used to change the AC voltage. Used when high power output is needed in a small space. |
| SODIMM: |
Small Outline DIMM, a small version of a DIMM used commonly in laptop computers. Whereas a full-size DIMM has 168 pins and supports 64-bit transfers, a SO DIMM has only 72 pins, which supports only 32-bit transfers, or 144 pins, which supports a full 64-bit transfer. |
| Soldering: |
A process that uses low-melting point metals to bond components to PCBs and so on. |
| Sound Card: |
An expansion board plugged into a motherboard to provide audio output from a computer; most also allow audio input. |
| SPDT: |
Single Pole, Double Throw (of switches or relays). |
| SPST: |
Single Pole, Single Throw (of switches or relays). |
| S-VHS: |
Super-VHS. Improved video tape format capable of recording better picture resolution, also used as a synonym for S-video. |
| S-video : |
A method of handling video signals using separate B&W (luma or Y) and colour (chroma or C) signals. Typically a 4-pin mini-DIN connector is employed, though some TVs use the SCART based S-video option. May also be labelled YC. |
| Switch: |
A passive component which passes or blocks electric current. |
| Tantalum Capacitor: |
High capacity/space ratio with average stability, ideal for coupling/decoupling applications. |
| Telescope: |
Astronomical tool. Telescopes increase the apparent angular size of objects. They also increase an objects, brightness. |
| Thermistor: |
A component whose resistance varies with the ambient temperature. |
| Thermometer: |
An instrument used for measuring temperature. |
| Thyristor: |
A four-layer semiconductor device, such as an SCR or triac. |
| Transformer: |
Used to step-up or step-down an AC voltage. |
| Transistor: |
A three terminal active component used in switching and amplifying circuits. |
| Triac: |
Triode AC switch; used for switching AC currents. |
| Tweeter: |
A small loudspeaker used to reproduce high frequencies. |
| UHF: |
Ultra High Frequency. Radio frequency in the range of 300MHz to 3GHz. |
| USB: |
Universal Serial Bus. A computer connection that is compatible with many types of devices, such as, printers, speakers, mice, etc. USB 1.0 can support speeds of up to 12Mbps whereas USB 2.0 is much faster at 480Mbps |
| Variable Resistor: |
Used in applications where resistance adjustment is necessary. |
| VHF: |
Very High Frequency. Radio frequency in the range of 30MHz to 300MHz. |
| VHS: |
Video Home System. Method of recording audio and video electrical signals onto magnetic tape. |
| Voltage: |
Measured in volts (V). The electromotive force (EMF) that causes current to flow. A potential difference of 1V causes a current of 1A to flow through 1Ω. |
| WAAS: |
WAAS (Wide Area Augmentation System) is a navigation aid developed by the Federal Aviation Administration to augment the Global Positioning System (GPS), with the goal of improving its accuracy, integrity, and availability. |
| Wi-Fi: |
Wireless Fidelity. Wireless local area network to IEEE 802.11b operating on 2.4GHz. |
| Woofer: |
A speaker that is designed to reproduce bass frequencies only. |
| XD Picture Card: |
One of several versions of small memory storage cards that uses flash memory to store information. Typically used in portable devices such as digital cameras. |
| XLR: |
A latching 3-pin connector typically used for balanced signals, such as those from a microphone. The confusion over whether pin 2 or 3 is hot has only relatively recently been resolved. The Standard is defined by the Audio Engineering Society in AES14-1992(r1998): pin 1 = Shield (Ground), pin 2 = Hot (In Phase or +), pin 3 = Cold (Out of Phase or -). To create an unbalanced connection, pin 1 and pin 3 are connected to ground and pin 2 carries the signal. It should be pointed out that there is a lot of equipment (particularly in the US) that has pin 2 and pin 3 designations reversed (i.e. 3 hot, 2 cold). Manufacturers are adopting the standard on all new equipment. |
| YC: |
See "S-video". |
| YCbCr: |
See "Component Video". |
| YPbPr: |
See "Component Video". |
| YUV: |
See "Component Video" |
| Zip drive: |
A storage device from Iomega that stores information on a type of floppy disk but with much higher capacity. |
