- B
- Acronym, Electronics: Beta
- Symbol, Magnetics: The symbol for magnetic flux density.
- Electronics: The current gain of a transistor in a common emitter circuit (a circuit with the emitter connected to ground). Also called hFE.
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- Back Reading
- Metal Detectors: A false signal caused by a rejected target coming within one inch of, or contacting, the bottom of the search coil when operating in the discriminate mode.
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- Balanced
- Audio: A circuit that uses two conductors and a shield for connection, in which first conductor carries the standard audio signal
and the second conductor carriers an inverted signal, which is
re-inverted and added to the first signal at the destination. This
inversion also inverts any line noise which is picked up by the cable,
so that the line noise is cancelled out. Compare to Unbalanced Line.
 Electronics: A circuit with two identical and symmetrical branches.
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- Balun
- Acronym: Balanced-unbalanced
- Communications, Electronics: A device used to couple a balanced device or line to an unbalanced device or line.
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- Banana Connector (Plug or Jack)
- Cables, Electronics: A connector that has a spring-metal tip and that is often used for speaker wiring. Also called a Binding Post. Click here for an illustration.
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- Band (or Frequency Band)
- Communications: A range of frequencies within a given range or used for a specific purpose.
- Electronics: A colored mark on resistors or other components, indicating the rating of that component.
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- Banding
- Digital Video: A color artifact caused when a gradual shading of colors in the original image is reduced to single-colored blocks or bands.
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- Band-pass Filter: see Filter, Band-pass.
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- Band-stop Filter: see Filter, Band-stop.
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- Bandwidth
- Communications: The frequency or frequencies allocated for an individual user, system or type of transmission.
- Computers: The amount of data that can be transferred through a network, usually measured in bits per second (bps).
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- Barograph
- Weather, Measurement: An instrument that continuously records a barometer's reading of atmospheric pressure.
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- Barometer
- Weather, Measurement: An instrument used to measure atmospheric pressure. Two examples are the aneroid barometer and the mercury barometer.
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- Barometer, Aneroid
- Weather, Measurement: An instrument for measuring the atmospheric pressure. It uses the change in the shape of an evacuated metal cell to measure variations on the atmospheric pressure. The aneroid capsule
is a thin-walled metal capsule or cell, usually made of phosphor bronze
or beryllium copper. The scales on the glass cover measure pressure in
both inches of mercury and millibars. Also called holosteric barometer.
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- Barometer, Mercury
- Weather, Measurement: An instrument used for measuring the change in atmospheric pressure.
It uses a long glass tube, open at one end and closed at the other.
After first filling the open end with mercury, it is then temporarily
sealed and placed into a cistern of mercury. A nearly perfect vacuum is
established at the closed end after the mercury descends. The height of
the column of mercury in the tube is a measurement of air pressure. As
atmospheric pressure increases, the mercury is forced from the cistern
up the tube; when the atmospheric pressure decreases, the mercury flows
back into the cistern. Measurement is taken in inches of mercury.
Although mercury barometers are very accurate, practicality has led
observers to use aneroid barometers. First used by Evangelista
Torricelli (1608-1647), an Italian physicist and mathematician, to
explain the fundamental principles of hydromechanics.
-
- Barometric Pressure: see Pressure, Barometric.
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- Barreling
- Digital Video: A distortion that occurs when using a wide-angle zoom lens and shows up as straight lines at the edges curving toward the center of the image.
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- Barrier Strip: see Terminal Strip.
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- Base
- Electronics, Transistors: The region that lies between the emitter and collector of a bipolar junction transistor (BJT).
- Electronics, Lamps: The bottom of a lamp or component, usually described as a type of base, such a Bayonet, Bi-pin, E-10, E-5, Flange, Threaded, or Wedge.
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- Baseband
- Audio, Video: A signal that is not modulated onto another carrier (such as being modulated to channel 3 or 4).
- Computers, Networking: A data transmission format where each conductor only carries a single channel. Compare to Broadband.
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- Base, Bayonet
- Electronics: A lamp base
with smooth sides and two small pins on opposite sides from one another
(so called because it slides into the socket and is turned to secure
it, in the same fashion as securing an old-style bayonet).
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- Base Biasing
- Electronics: A method of biasing a bipolar junction transistor (BJT) in which the bias voltage is supplied to the base by means of a resistor.
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- Base, Bi-pin
- Electronics: A lamp base that has two long pins extending from the bottom of it.
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- Base, E-10
- Electronics: A threaded lamp base that uses an E-10 thread.
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- Base, E-5
- Electronics: A threaded lamp base that uses an E-5 thread.
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- Base, Flange
- Electronics: A lamp base that has smooth sides and a flange or rim where the base and lamp meet.
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- Base Station
- Communications: A non-mobile scanner or two-way radio that is often connected to a larger, outdoor antenna.
- GPS: A station designed to allow the operator to monitor and control operation of the GPS system.
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- Base, Threaded
- Electronics: A lamp base designed to screw into a corresponding socket, usually identified by the thread type, such as E-10 or E-5.
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- Base, Wedge
- Electronics: A lamp base in which the bottom of the glass has been crimped down to form a flat wedge.
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- Basic Trading Area: see BTA.
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- Bass
- Audio: The audio frequencies up to approximately 500 Hz, or a control designed to adjust the playback or recording of these frequencies.
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- Bass-reflex: see Enclosure, Vented.
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- Battery
- Batteries: A DC voltage source containing two or more cells that convert chemical energy to electrical energy.
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- Baud, Baud Rate: See bps.
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- Bayonet Base: see Base, Bayonet.
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- Bayonet Connector: See BNC.
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- Bayre
- Measurement: Cgs unit for pressure; equal to 0.1 Pascal.
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- Beat-frequency Oscillation: see BFO.
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- Beaufort Wind Scale
- Weather: A system of estimating and reporting wind speeds.
It is based on the Beaufort Force or Number, which is composed of the
wind speed, a descriptive term, and the visible effects upon land
objects and/or sea surfaces. The scale was devised by Sir Francis
Beaufort (1777-1857), hydrographer to the British Royal Navy. A copy of the scale is available in our Basic Guide to Weather.
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- Beaver Tail
- Metal Detectors: The tail of a pull-tab separated from the ring, which usually gives the same signal as nickels and gold rings.
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- Bench Test
- Metal Detectors: An air test
to determine at what approximate discriminate settings various metal
samples are rejected or accepted. The test is conducted in a
non-metallic area.
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- Beta
- Video: A video tape format introduced by Sony® in 1975. RadioShack still carries Beta L-750 Cassettes as catalog number 44-482.
- Computer, Software:
A software or hardware version that is mostly working but is still
being tested. Hardware and software often go through two stages of
release testing, alpha (in-house) and beta (limited release), before
being sold.
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- BFO
- Acronym: Beat-Frequency Oscillation
- Metal Detectors: The most basic type of detector, BFO detectors use two coils: one large coil in the search head and a smaller coil in the control housing. Each coil is connected to an oscillator
which generates a steady frequency, with each coil having a slightly
different frequency. This difference in frequencies will cause a steady
"beat" which can be picked up by the receiver in the control box. Any
metal or mineral in range of the signal will interfere with the
frequency in the search coil, causing a change in the duration and tone of the beat frequency.
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- Bias, Biasing
- DIY, Electronics: An electrical signal applied to a component in order to establish a reference level for operation.
-
- Bias, Forward: see Voltage, Forward
-
- Bidirectional
- Literally, operating in two directions.
- Audio, Video, Communications: Refers to antennas that are designed to receive signals along a straight line (forward and backwards) from the antenna.
- Computers: Used to describe a port (usually a parallel port) that allows two-way communication between the computer and the attached device.
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- Binding Post: see Banana Connector (Plug or Jack).
-
- Bi-pin Base: see Base, Bi-pin.
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- Bipolar
- DIY: A semiconductor, such as a transistor, in which both negative and positive charge carriers are used. Compare to Unipolar.
-
- Bipolar Junction Transistor: see BJT.
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- Birdie
- Communications: A false/unwanted signal produced by the electronics inside a scanner.
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- Bit
- Acronym: Binary digit
- Computers: The smallest unit of information on a computer. Bits are usually designated either a 0 or 1 (representing on/off states).
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- Bit Depth
- Digital Video: The color or gray scale of an individual pixel. A pixel with 8 bits per color gives a 24 bit image. (8 bits x 3 colors is 24 bits.) 24 bit color resolution is 16.7 million colors.
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- Bitmap
- Digital Video: A method of storing image information that maps each pixel, bit by bit.
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- Bit Rate
- Digital Audio: The number of bits played each second, usually expressed as kbps (kilobits per second). The bit rate is used as a measurement of resolution of the recording of the music file. MP3's
are generally recorded at 128 kbps for the best compromise between
speed and file size.The higher the bit rate, the higher the quality of
the audio playback and the larger the file.
-
- BJT
- Acronym: Bipolar Junction Transistor
- Electronics: A three-terminal device in which the current from the emitter to the collector is controlled by the base current.
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- Black Sand
- Metal Detectors: One of the most extreme components of non-conductive, negative ground minerals. Also called magnetite and magnetic iron oxide.
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- Blizzard
- Weather: A severe weather condition characterized by low temperatures, winds of 35 mph or greater, and sufficient falling and/or blowing snow
in the air to frequently reduce visibility to 1/4 mile or less for a
duration of at least 3 hours. A severe blizzard is characterized by
temperatures near or below 10°F, winds exceeding 45 mph, and visibility
reduced by snow to near zero.
-
- Block Diagram
- A
system diagram that illustrates the general operation and interaction
of the primary elements using blocks to represent each element. Compare
to a Circuit Diagram, which illustrates the specific operation of all elements.
-
- Blooming
- Digital Video: A visual effect caused by overexposing a CCD sensor, that can cause distortions of the subject and/or color.
-
- Bluetooth™
- Telephony:
A technology specification for small-sized, low-cost, and short-range
radio links designed to operate between mobile PCs, mobile telephones,
and other portable devices. Additional information is available on the Bluetooth™ website.
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- BMI®
- Acronym: Broadcast Music Inc.
- Audio: A non-profit performing-rights organization.
-
- BMP
- Acronym: BitMaPped Image
- Digital Video: An uncompressed bitmapped file format used with Microsoft® Windows®.
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- BNC
- Acronym: Bayonet Neill Concelman (after inventors Paul Neill & Carl Concelman)
- Audio, Video, Communications: A connector often used in audio/video and communications (click here for an illustration). The threaded version is called a TNC connector.
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- Body Mount
- Metal Detectors: A method of fastening the detector's control housing to expand usability for shallow water hunting. Also known as hip mount.
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- Boiling Point
- Weather: The temperature
at which a liquid changes to a vaporous state. The temperature at which
the equilibrium vapor pressure between a liquid and its vapor is equal
to the external pressure on the liquid. The boiling point of pure water
at standard pressure is 100°C or 212°F.
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- Bootleg
- Audio:
To produce, distribute, or sell an unofficial copy of a musical
recording, or an original but illegal recording. Also referred to as pirate.
-
- Boundary Microphone: see Microphone, Boundary.
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- BPM
- Acronym: Beats Per Minute
- Digital Audio: A parameter for digital music that refers to the tempo of a song.
-
- bps
- Acronym: bits per second (with lower-case "b")
- Measurement, Computers: A unit of measurement used to describe the speed of data flow in a digital signal. Also called Baud or Baud Rate.
-
- Bps
- Acronym: Bytes per second (with upper-case "B")
- Measurement, Computers: A unit of measurement used to describe the speed of data flow in a digital signal.
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- Breakdown Voltage: see Voltage, Breakdown.
-
- Breakover Voltage: see Voltage, Breakover.
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- Bridge Rectifier: see Rectifier, Bridge.
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- Brightness
- Video: see Luminance.
- Digital Video: The value of a pixel
in an digital image, representing its lightness value from black to
white. Usually defined as brightness levels ranging in value from 0
(black) to 255 (white).
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- Broadband
- Internet: A communications channel that has a bandwidth greater than 64 kbps (kilobits per second) and that can provide higher speed data communications than a standard telephone circuit . Examples of broadband Internet connections include cable access, DSL, and T-1 and T-3 lines.
- Computers, Networking: A data transmission format where a single conductor carries multiple channels. Compare to Baseband.
- Telephony:
The information capacity of a telecommunications channel. Broadband
communications generally indicates a bandwidth higher than 2 Mbps.
-
- Broadband Amplifier: see Amplifier, Wideband.
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- Browser
- Internet: A software application, such as Netscape® or AOL®,
used to locate and display Web pages. With a browser, users can access
and explore the World Wide Web, locate files--including MP3 files--and play them by configuring the browser to support other pieces of software such as MP3 players.
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- BTA
- Acronym: Basic Trading Area
- Telephony: A subset of a Major Trading Area, that consists of multiple BTA's. See MTA.
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- Buffer
- Computers: A temporary storage area usually held in RAM and used as a temporary holding area for data.
-
- Burn
- Computers: The process of permanently archiving data to a blank CD (compact disc). CD drives that are used to write data to blank CD's are called "CD burners" or "CD writers."
-
- BURN-Proof™
- Acronym: Buffer Underrun Proof
- Computers: A technology was developed by Sanyo Electric Co. Ltd.® to combat the most common problem in burning
CD's. If a data stream is interrupted while burning, the CD creation
process is often ruined. BURN-Proof combats this by creating a seamless
data stream.
-
- Burst Mode
- Digital Video: Refers to a digital camera's ability to rapidly capture images as long as the shutter button is held down.
-
- Bus
- Computers, Networking: A network topology in which the computers are connected as illustrated below. See also Ring, Star, Mesh, Tree.

-
- Business Band
- Communications:
Refers to the frequencies or radios used for the Industrial/Business
Radio service. Business band frequencies are those listed as BUS or IND on the Frequency Band Allocation table. RadioShack sells a number of Business Band radios and accessories.
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- Buzzer, Ceramic
- Electronics: A piezo buzzer using a ceramic piezo element.
-
- Buzzer, Piezo
- Electronics: A buzzer that uses a piezo element to produce sound.
-
- B'-Y'
- Video: The color difference between the blue component and the luma -- Cb' in the YCbCr color space and Pb' in the YPbPr color space.
-
- Byte
- Computers: A unit of measurement that is used to describe storage capacity. One byte of memory is equal to eight bits. Large amounts of memory are indicated in terms of kilobytes (KB = 1024 bytes), megabytes (MB = 1024 kilobytes), and gigabytes (GB = 1024 megabytes).
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