1.
3G : Third-generation
mobile telephone protocols that support higher data rates, for non-voice
communications such as multimedia and Internet access.
2.
A : It
is used as symbol for Area, ampere.
3.
Abnormal
propagation : It is the Phenomena of changing
atmospheric or ionospheric conditions acting upon transmitted radio waves.
4.
Abnormal
reflections : these are reflections of radio
waves at frequencies above the critical frequency of the ionized layer of the
ionosphere.
5.
Abnormal : it means not normal; not typical, usual.
6.
Absolute delay : the
difference of the time interval between two transmitting signals from same or
different stations.
7.
Absolute Gain :
The ratio of the signal level at the output of the device to that of its input
under a specified set of operating conditions
8.
Absolute scale : It
is the scale which is used to measure the temperature in Celsius scale and it
pointed as zero while the temperature is zero.
9.
Absolute temperature : the
temperature measured on the absolute scale.
10.
Absorption loss : the
transmission loss caused by the dissipation or conversion of electrical,
electromagnetic, or acoustic energy into other forms of energy as a result of
its interaction with a material medium.
11.
Absorption : the
process of taking anything from other./ The loss or dissipation of energy as it
travels through any medium.
12.
AC
Coupling. The interconnection between two circuits through a capacitor or
other device which passes AC voltage but blocks any DC component.
13.
Ac coupling: A
method of coupling one circuit to another through a capacitor or transformer so
as to transmit the varying (ac) characteristics of the signal while blocking
the static (dc) characteristics.
14.
AC
generator. [Alternator] A rotating machine that converts mechanical energy
into alternating current.
15.
Accelerating
Anode : An electrode charged several thousand volts positive and used to
accelerate electrons toward the front of a Cathode-Ray Tube.
16.
Accelerating
electrode : It is an electrode which is used
in cathode ray tube to increase the velocity of the electrons.
17.
Accelerating
electrode: The electrode that causes electrons emitted from an electron gun to
accelerate in their journey to the screen of a cathode ray tube.
18.
Accelerating
voltage: The voltage applied to an electrode that accelerates a beam of
electrons or other charged particles.
19.
Acceleration
Servosystem : A servo-system that controls the acceleration (rate of
change in velocity) of a load.
20.
Acceleration : the
rate of change of velocity with respect to time.
21.
Accelerometer : it
is a measuring instrument which can measure the acceleration of aircrafts and
rockets.
22.
Acceptable
reliability level: The maximum number of failures allowed per thousand
operating hours of a given component or system.
23.
Acceptance
angle : it
is the maximum angle at which the core of the fiber will take in light that
will be contained within the core.
24.
Acceptor
impurity : it is an atom or molecule that receives one or more
electrons from another atom or molecule, resulting in a chemical bond or flow
of electric current.
25.
Acceptor : it
is an atom or molecule that receives one or more electrons from another atom or
molecule, resulting in a chemical bond or flow of electric current.
26.
Access
- In computer terms, to obtain data from a storage device.
27.
Access control : It
is a technique used to permit or deny use of the components of a communication
system.
28.
Access point : In
wireless communication, it is devices which can be connect with the network.
29.
Access Time. The
difference in time between when data is requested and when data is delivered.
The time lapsed between a given command and when the function is performed. The
time for the [disk drive] access arm to reach the desired track and the delay
for the rotation of the disk to bring the required sector under the read-write
mechanism.
30.
Access : The
ability and means necessary to store data in, to retrieve data from, to
communicate with, or to make use of any resource of a system.
31.
Accumulator
register : a register that has a built-in
adder that adds an input number to the contents of the register.
32.
Accumulator : a
register that has a built-in adder that adds an input number to the contents of
the register.
33.
Accumulator : It
is a register in a computer used for holding the results of a computation or
transferred data.
34.
Accumulator. A
register that both stores a number and adds to other numbers loaded into the
register.
35.
Accuracy : It
is the quality of being near to the true value.
36.
Acknowledgement : A
message from the addressee informing the originator that has been received or
not.
37.
Acoustic filter : A
device which can reject sound in a particular range of frequencies while
passing sound in another range of frequencies.
38.
Acoustic wave : A
longitudinal wave that (a) consists of a sequence of pressure pulses or elastic
displacements of the material, whether gas, liquid, or solid, in which the wave
propagates.
39.
Acoustic : the sense of hearing, or the science of sound.
40.
ACPI
- Advanced Configuration and Power Interface. An industry standard for
power management of computers. This configuration is controlled through the
bios and / or software settings.
41.
Acquisition
time : According
to communication system, it is the time taken by antenna to take the signal
from the satellite.
42.
Acquisition : It
means gaining or acquires something from the other. For example while
considering antenna it is the process of receiving data from satellite.
43.
Active circuit : An
electronic circuit which uses active devices such as transistors or integrated circuits
for its operation.
44.
Active
component : The circuit element that switches the flow of current
or gain. Examples: transistors, diodes, vacuum tubes.
45.
Active elements : These
are the elements which are capable of delivering power to some external device
or circuit. Examples for these are voltage source and current source.
46.
Active filter : it
is a type of analog filter, distinguished by the use of one or more active
components i.e. voltage amplifiers or buffer amplifiers.
47.
Actuating
force. The force applied to the actuator to operate the contacts. The
force required to operate a mechanical switch.
48.
Actuator -
A device that converts an electronic signal into a mechanical motion.
49.
Actuator : While considering control systems. It is the mechanism
to activate process control equipment by use of pneumatic, hydraulic, or
electronic signals; for example, a valve actuator for opening or closing a
valve to control the rate of fluid flow.
50.
Actuator. The
part of a switch that is
acted upon to cause the switch to change contact connections; for example,
toggle, pushbutton, and rocker. The mechanism of the switch or housing which,
when moved as intended, will operate the contacts.
51.
Adder. A
circuit that adds two or more numbers together.
52.
Additive white
Gaussian noise (AWGN): Noise that is additive to the signal having a constant
power spectrum over all frequencies and Gaussian amplitude distribution.
53.
Address
- In internet terms, the "web address" identifies the specific
location of an internet site. In computer terms, address identifies where data
is located.
54.
Address Bus : The
collection of wires over which the CPU sends a memory location to the I/O
device.
55.
Address
Bus. The portion of an interface bus that carries the address of the node
being selected. In most cases the address bus are pins separate from those that
carry the data, but in some cases the address bus and data bus are time
multiplexed on the same pins.
56.
Address
Field. The portion of a message that contains the source-user address and
the destination-user addresses.
57.
Adjacent
channel interference: Interference to communications caused by a transmitter
operating on an adjacent radio channel. The sidebands of the transmitter mix
with the carrier being received on the desired channel, resulting in noise.
58.
Adjacent
Channel. A frequency band immediately above or below a band of frequencies
being used [as a channel]. Two or more analog communication paths spaced near
each other.
59.
Administrator - A
power user who control everything on a website.
60.
ADSL
- Asymmetric Digital Subscriber Line. A set of DSL technologies that
allocate more bandwidth in one direction than the other.
61.
Air-Core
Inductor. An inductor composed of two or more coils that are wound around
a non-metallic core. Normally air-core inductors are found in RF applications.
62.
Air-Core
Transformer. A transformer composed of two or more coils that are wound
around a non-metallic core. Air-core transformers are lossless and don't suffer
from heating due to eddy currents losses.
63.
Aliasing:
Distortion arising from the representation of a signal by its samples due to
too low a sampling rate relative to the signal bandwidth.
64.
Alloy - A
metal formed by the combination of two or more metals.
65.
Alloy. A
mixture of two or more materials, at least one of which is a metal.
66.
All-Pass
Filter. An active or passive filter that passes all frequencies applied to
it, but normally applies a phase shift between the input and output.
67.
Alternating
Current - An electric current that reverses direction at regular
intervals, having a magnitude that varies continuously in a sinusoidal manner.
68.
AM
Receiver. A receiver that decodes an Amplitude Modulated signal to recover
encoded information.
69.
AM Rejection
Ratio. The ratio of the recovered audio output produced by a desire FM
signal of specified level and duration to the recovered audio output produced
by an unwanted AM signal of specified amplitude and modulating index.
70.
Ambient level:
The magnitude of radiated or conducted electromagnetic signals and noise at a
specific test location when equipment-under-test is not powered.
71.
Ambient Noise
Level. The level of acoustic noise existing at a given location, such as
in a room, in a compartment, or at a place out of doors.
72.
Ambient
Temperature - The temperature surrounding an object.
73.
Ambient
Temperature. The temperature of the air or liquid surrounding any object.
The surrounding temperature such as the temperature of air surrounding a
conductor in a compartment or within a piece of equipment. Ambient temperature
is the air temperature measured below a [semiconductor] device, in an
environment of substantially uniform temperature, cooled only by natural air
convection, and not materially affected by reflective and radiant surfaces.
74.
Ambient temperature:
The temperature of the surrounding medium, typically air, that comes into
contact with an apparatus. Ambient temperature may also refer simply to room
temperature.
75.
Ammeter : An electric meter used to measure current, can be
measured in amperes.
76.
Ampere : It
is the units for current.
77.
Amplification
Factor. The voltage gain of an amplifier with no load on the output.
78.
Amplification : The
Process of increasing the amplitude of a weak signal without change in its
frequency and shape.
79.
Amplifier
Nonlinearity. The inability of an amplifier to reproduce an output which
is proportional to the input.
80.
Amplitude
modulation : The process of varying the
amplitude of carrier signals with respect to message signal is called amplitude
modulation.
81.
Amplitude
Modulation. Modulation in which the amplitude of a carrier wave is varied in
accordance with some characteristic of the modulating signal.
82.
Amplitude
Stability. Amplitude stability refers to the ability of the oscillator to
maintain a constant amplitude in the output waveform.
83.
Amplitude-shift
keying (ASK): A signaling scheme whereby the digital data modulates the
amplitude of a carrier.
84.
Analog
Decoding. The portion of the digital-to-analog conversion process that
generates an analog signal value from the digital signal that resulted from
analog encoding.
85.
Analog
Encoding: The portion of the analog-to-digital conversion process that
samples an analog signal and creates a digital signal that represents the value
of the sample.
86.
Analog pulse
modulation : In this process we can vary the amplitude, duration,
position, of the pulses with respect to the message signal.
87.
Analog
Signal. A signal that has a continuous nature rather than a pulsed or
discrete nature.
88.
analog -
Information represented as continuously varying voltage or current rather than
in discrete levels as opposed to digital data varying between two discrete
levels.
89.
Analog-to-Digital
Converter. [ADC] A device that converts an analog signal to a digital
signal that represents equivalent information.
90.
AND
Gate. A binary circuit, with two or more inputs and a single output, in
which the output is logic 1 only when all inputs are logic 1 and the output is
logic 0 when any one of the inputs is logic 0.
91.
Angle
modulation : the process of varying the angle of carrier signal with
respect to the message signal is called angle modulation.
92.
Angle
Modulation. Modulation in which the angle of a sine-wave carrier is varied
by a modulating wave. Modulation in which the phase or frequency of a
sinusoidal carrier is varied.
93.
Angle of Deflection. The
angle of an electron beam induced by the deflection coils of a Cathode Ray
Tube.
94.
Anode - The
positive electrode that emits positive ions and attracts negative ions, within
a voltaic cell or other such device. / The positive pole of a battery.
95.
ANSI
- American National Standards Institute. Organization that sets standards
for how things are manufactured or procedurally done.
96.
Antenna
- Metal device which picks up and delivers signals to a receiver; most
commonly used for receiving radio signals.
97.
Antenna
Coupler. A device used for impedance matching between an antenna and a
transmitter or receiver.
98.
Antenna for
receiving - A device that converts a radiated electromagnetic wave into an
electrical wave.
99.
Antenna for
transmitting - A device that converts an electrical wave into an
electromagnetic wave that radiates away from the antenna.
100. Antenna Gain - An antenna's transmission power, provided
as a ratio of its output (send) signal strength to its input (receive) signal
strength, normally expressed in dBi. The higher the dBi, the stronger the
antenna.
101. Antenna Gain. A measure of the output of an antenna compared
to a standard antenna using the same frequency.
102. API - Application Program Interface. In terms of programming,
this refers to a set of functions or routines that allows interface with an
operating system (i.e. - dll files)
103. Arithmeticmean: The sum of the values of several quantities
divided by the number of quantities, also referred to as the average.
104. ASCII - American Standard Code for Information Interchange. A
type of 8 digit code that represents the letters of the alphabet and
other characters. On a keyboard, each key represents a different ASCII code.
Sometimes pronounced ASK-TWO or ASKEE.
105. Aspect Ratio - The numerical relationship of height to width
on a television screen
106. Aspect Ratio. The ratio between the width of an object and
the height of the object. The 4:3 aspect ratio of a traditional TV or monitor
or the 16:9 aspect ration for newer monitors.
107. Assembly Language - A translation of machine binary code into
a form easier to read for human use.
108. Asynchronous - Data stream that is sent with start and stop
bits (this shows where the data began and ended). This data transmission method
uses flow control rather than a clock to synchronize data.
109. Asynchronous Communication. Communication in which no
clocking information is passed between stations.
110. Asynchronous Communications System. A data communications
system that uses asynchronous operation.
111. atomic number - The number of positive charges or protons in
the nucleus of an atom.
112. Attenuation - The loss of electrical signal from where it
began (i.e. - How much signal loss occurs over a length of cable).
113. Attenuator - An electronics device (resistors) used to reduce
signal or power strength
114. Attenuator. A resistive component inserted into a circuit to
reduce signal amplitude. A network that reduces the amplitude of a signal
without appreciably distorting its waveform.
115. Attraction. The force that tends to make two objects approach
each other. Attraction exists between two unlike magnetic poles (north and
south) or between two unlike static charges.
116. Automatic Gain Control. [AGC] A circuit used to limit
variations in the output signal strength of a receiver. A process or means by
which gain is automatically adjusted in a specified manner as a function of a
specified parameter, such as received signal level.
117. Autotransformer : A transformer used to step
voltage up or down. The primary and secondary windings share common turns, and
it provides no isolation.
118. Avalanche Break Down : In reverse biased PN junction,
ionization by collision is known as Avalanche break down.
119. AWG - American Wire Gauge. An American standard which sets
the diameter of wire (i.e. 16 gauge wire).
120. Back emf: A voltage induced in the reverse direction when current
flows through an inductance. Back emf is also known as counter-emf .
121. Background Noise. The total system noise in the absence of a
signal
122. balanced bridge - Condition that occurs when a bridge circuit
is adjusted to produce a zero output.
123. Ball Grid Array - A type of chip package where the
fixing method consists of a number of solder balls mounted under the chip and
directly soldered onto a PCB.
124. Bandgap: Energy difference between the conduction band and the
valence band.
125. band-pass filter - A tuned circuit designed to pass a band of
frequencies between a lower cut-off frequency (f1) and a higher cut-off
frequency (f2). Frequencies above and below the pass band are heavily
attenuated.
126. Bandpass Filter. A filter that allows a narrow band of
frequencies to pass through the circuit. Rejects or attenuates frequencies that
are either higher or lower than the desired band of frequencies.
127. Band-Reject Filter. A tuned circuit that does not pass a
specified band of frequencies.
128. band-stop filter - A tuned circuit designed to stop
frequencies between a lower cut-off frequency (f1) and a higher cut-off
frequency (f2) of the amplifier while passing all other frequencies.
129. Band-Stop Filter. A tuned circuit that does not pass a specified
band of frequencies.
130. Bandwidth - The data carrying capacity of a transmission
path, measured in bits or bytes per second.
131. Bandwidth : It is the range of frequency over
which the gain is equal to or greater than 70.7% of maximum gain.
132. barrier potential - The natural difference of potential that
exists across a forward biased pn junction.
133. Barrier Potential : Potential developed adjacent to
PN junction due to electron hole recombination.
134. Baseband signal : It is the signal designated with
band of frequencies which is used for carrying the message signal.
135. BASIC - Beginners All-purpose Symbolic Instruction Code. A
very simple computer programming language.
136. Batch file - A type of file used to automate tasks, namely
operating system startup. This file executes commands that can start several
programs at once.
137. Battery Capacity. The amount of energy available from a
battery. Battery capacity is expressed in ampere-hours.
138. Battery - A combination of two or more chemical cells
connected together electronically to produce electrical energy.
139. Baud Rate - The unit of measure for how fast a modem
operates.
140. Baud - A unit of measure for data transmission rate expressed
in bits per second.
141. Beam Splitter: A device for dividing an optical beam into two
or more separate beams.
142. Bend Loss. The attenuation of a signal that results from
bending a fiber optic cable.
143. Bend Radius. The minimum radius to which a cable, without
tensile load, can be bent for its lifetime without causing broken wires or
fibers, a localized weakening of the fibers, or a permanent increase in
attenuation.
144. BGA - Ball Grid Array. A
type of chip package where the
fixing method consists of a number of solder balls mounted under the chip and
directly soldered onto a PCB.
145. Bias Compensation : It is the technique makes use of
temperature sensitive devices such as diodes, transistor, thermistors,
sensistors etc. in such a way as to introduce compensating changes to stabilize
the operating point.
146. Bi-CMOS. An integrated circuit that combines both bipolar
junction transistors and complementary MOS transistors [CMOS].
147. Bilateral Elements : These are the elements, which are
having voltage-current relation is same for current flowing in both directions.
Resistors are examples for these elements.
148. Binary Code: a coding scheme that communicates information by
using a series of "1s" and "Os" that are represented,
respectively, by the digital "ON" and "OFF" states
149. Binary: the basic counting system used in computer logic. Two
values are available - 0 and 1. A zero is normally represented by a 0 Volt
signal, and a one by a voltage of approximately 5 Volts - these levels are
dependent upon the type of logic used
150. Bipolar Junction Transistor : It is a solid-state device in which the current flow
between two terminals (collector and emitter) is controlled by the amount of
current that flows through a third terminal (base).
151. bistable multivibrator - A multivibrator with two stable
states. An external signal is required to change the output from one state to
the other.
152. Bit Error Rate. The number of error bits [bits received in error]
divided by the total number of bits transmitted, received or processed over
some stipulated period. Also found as Bit Error Ratio
153. Bit: a unit of the binary code that consists of either a
single "1" or "O".
154. BJT : It’s full form is Bipolar Junction
Transistor, it is a solid-state device in which the current flow between two
terminals (collector and emitter) is controlled by the amount of current that
flows through a third terminal (base).
155. Bluetooth - A wireless computing and telecommunications
specification that defines how mobile personal computing devices work with each
other and with regular computers and phone systems within a close range.
156. Bolometer. A loading device that undergoes changes in
resistance as changes in dissipated power occurs.
157. Branch : when two or more elements/sources
connected in series to form a two terminal device is called Branch.
158. Bread Board - Board made of pertinax or other insulating material
for building prototype circuits. It contains a matrix of holes. There are also
types with soldering pads around the holes, these cost more but are easier to
work with.
159. Breakdown Voltage - The voltage at which a dielectric
material fails.
160. bridge rectifier - A circuit using four diodes to provide
full wave rectification. Converts an AC voltage to a pulsating DC voltage.
161. Bridge Rectifier : It is a full wave rectifier
circuit which employs 4 diodes connected in the form of bridge to provide
rectification.
162. Broadband Satellite - Satellite and ground based station
system used to deliver high speed internet access to small dish receivers
163. Broadcasting : Transmitting signal from one
transmitter to multiple receivers called broadcasting.
164. Browser - A software program that displays relevant
information and allows navigation. The most common browser is an internet
browser which displays web sites and allows navigation of the internet. There
are other types of browsers such as picture and programming browsers.
165. Buffer - A term used to describes a temporary storage area
for data. It is stored in this buffer before it can be processed. Buffering
speeds up data processing.
166. Bus : Data
path that connects to a number of devices. A typical example is the bus a
computer's circuit board or backplane. Memory, processor, and I/O devices may
all share the bus to send data from one to another.
167. Bypass capacitor: A capacitor that provides a signal path that
effectively shunts or bypasses other components.
168. Byte: a unit of the binary code that consists of eight bits.
169. Cabinet : An enclosure that is designed for
either surface mounting or flush mounting and is provided with a frame, mat, or
trim in which a swinging door or doors are or can be hung.
170. Cable Modem - A modem that receives data through cable
television systems
171. cable - Group of two or more insulated wires.
172. Calorimeter : An instrument use to measure the
heat generated by an electrical current in a conductor.
173. Capacitance - The measure of the amount of electrical charge
that is held by a capacitor. Measured in farads.
174. Carbon Microphone. A microphone in which sound waves vary the
resistance of a pile of carbon granules.
175. Carbon Resistor. A resistor that uses either a slug of carbon
or a film impregnated with carbon as the resistive element.
176. Carrier frequency : the frequency of the carrier is
called carrier frequency.
177. Cascade Amplifier. Two or more amplifiers connected together,
with each output connected to the input of the following stage.
178. Cascading : It is the technique used to
connecting several amplifier stages such as the output of one stage forms the
input of next stage.
179. Cascading. Connecting two or more circuits together so that
one circuit feeds the other.
180. Case Temperature. The temperature measured at a specified
point on the case of a semiconductor device
181. center tapped rectifier - Circuit that make use of a center
tapped transformer and two diodes to provide full wave rectification.
182. Center-Tapped Transformer. A Transformer with a tap on the
secondary winding mid-way between the winding producing half the available
output voltage.
183. Central limit theorem : It states that the probability
distribution of random variable approaches a normalized Gaussian distribution in
the limit as the number of random variables approaches infinity.
184. Ceramic Capacitor. A capacitor that uses a ceramic material
as a dielectric.
185. Channel Capacity: The maximum possible information transfer
rate through a channel.
186. Channel code word : in digital communication the
channel encoder encodes the source code word the resultant sequence of symbols
is called channel code word.
187. Character Interval. In a communications system, the total
number of unit intervals required to transmit any given character
188. Characteristic Curve. An input output curve that describes
the function of a component or circuit.
189. Characters per Second. [cps] A unit of signaling speed used
to express the number of characters passing a designated point per second.
190. Charge (Battery) - The conversion of electrical energy
from an external source, into chemical energy within a cell or battery.
191. Check Bit. A bit, such as a parity bit, derived from and
appended to a bit string for later use in error detection and possibly error
correction.
192. Check Character. A character derived from and appended to a
data item, for later use in error detection and possibly error correction.
193. Circuit Element : Any circuit component with two
terminals is called circuit elements. Ex are resistor, capacitor, inductor, voltage
source, current source.
194. Circulator. A passive junction of three or more ports in
which the ports can be accessed in such an order that when power is fed into
any port it is transferred to the next port, the first port being counted as
following the last in order.
195. Cladding - The layer of glass that surrounds the optic fibers
in fiber optic cables.
196. Cladding. The dielectric material surrounding the core of an
optical fiber. A low refractive material that surrounds the core of the optic
fiber and protects against scattering. Fiber cladding might be glass or
plastic.
197. Clamper Circuit : A circuit that places either the
positive or negative peak of a signal at a desired d.c. level is known as
clamping circuit.
198. Clamping Diode. A diode used to limit the peak voltage on a
line to a pre-determined maximum voltage.
199. Class A amplifier - A linear amplifier biased so the active
device conducts through 360 degrees of the input waveform.
200. Class AB amplifier - An amplifier in which the active device
conducts for greater than 180 degrees but less than 360 degrees of the input
waveform cycle.
201. Class B amplifier - An amplifier with two active devices. The
active components are biased so that each conducts for approximately 180
degrees of the input waveform cycle.
202. Class C amplifier - An amplifier in which the active device
conducts for less than 180 degrees of the input waveform cycle.
203. Clipper - a
nonlinear electronic circuit whose output is limited in amplitude; used to limit
the instantaneous amplitude of a waveform.
204. Clipper Circuit : The circuit with which the
waveform is shaped by removing or clipping a portion of the applied wave is
known as clamping circuit.
205. Coaxial Cable: a metallic cable constructed in such a way that
the inner conductor is shielded from EMR (electromagnetic radiation)
interference by the outer conductor. Coaxial cable is less susceptible to more
transmission impairments than twisted pair cable, and it has a much greater
bandwidth; thus coaxial cable is used by most analogue and digital systems for
the transmission of low level signals.
206. COBOL - Common Business Oriented Language. A programming
language for business applications.
207. Code Conversion. Conversion of signals, or groups of signals,
in one code into corresponding signals, or groups of signals, in another code.
208. CODEC: COder / DECoder - the component of any digital
subsystem which performs analogue to digital and digital to analogue
conversions.
209. Code-Division Multiple Access. [CDMA] A coding scheme, used
as a modulation technique, in which multiple channels are independently coded
for transmission over a single wideband channel.
210. Coherence. A definite phase relationship between two energy
waves, such as transmitted frequency and reference frequency.
211. Cold-Cathode Tube. A gas-filled electron tube that conducts
without the use of filaments. Cold-cathode tubes are used as voltage
regulators.
212. Colour Code: used to identify resistors and some capacitors,
as well as wires in telephony
213. Combinational logic: A logic circuit without memory elements.
214. Common Base. The Base element is common to both the input and
output circuit, normally grounded.
215. Common Collector. A transistor circuit which has the
collector of the transistor grounded or common between the input and output of
the transistor circuit.
216. Common Emitter. A transistor circuit that has the Emitter pin
common to both the input and output side.
217. Common-mode rejection ratio - (CMRR) The ratio of op-amp
differential gain to common-mode gain. A measure of an op-amp's ability to
reject common-mode signals such as noise.
218. Communication channel : The medium which is used to
transfer of information from one point to other point is called communication
channel.
219. Communication : It is the process of convey
message from one point to other point is called communication.
220. Commutative Law. In Boolean algebra this law states that
changing the order of the terms in an equation will not affect the value of the
equation. Example: A + B = B + A; A x B = B x A.
221. Compact Disk. [CD] An optical disk used to store digital
data, such as text, sound or video. A Compact Disk player is used to store or
retrieve the information.
222. Compander : Signal
processing technique which uses both compression and expansion to improve
dynamic range and signal-to-noise ratio.
223. Companding. An operation in which the dynamic range of
signals is compressed before transmission and is expanded to the original value
at the receiver.
224. Comparator. A component that compares two analog variables
and indicates the result of that comparison
225. Compensation Theorem : It states that any element in the
liner, bilateral network, may be replaced by a voltage source of magnitude
equal to the current passing through the element multiplied by the value of the
element, provided the currents and voltages in other parts of the circuit
remain unaltered.
226. Complement. A number or state that is the opposite of a
specified number or state. The negative of a number is often represented by its
complement. An inversion, a logic gate that outputs a low [or high] when
presented with a high [or low].
227. Complementary Law. In Boolean algebra this law states that
the logical addition of a quantity and its complement will result in 1 and the
logical multiplication of a quantity and its complement will result in a
product of 0.
228. Complex numbers - Numbers composed of a real number part and
an imaginary number part.
229. Complex Tone. A sound wave composed of a number of sine waves
of different frequencies.
230. Complex Wave. A waveform other than a sine wave. A wave that
is produced by combining two or more pure tones at the same time.
231. Compliance - The maximum possible peak-to-peak output of an
amplifier.
232. Composite Video. A video signal in which synchronizing
information (pulses) and picture information, including chroma, i.e., color,
information are combined.
233. Compressor. A nonlinear analog device that has a lower gain
at higher input levels than at lower input levels.
234. Computer. A data processing unit that can perform
computation, including numerous arithmetic or logic operations, without
intervention by a human.
235. Conductive Coupling. Energy transfer achieved by means of
physical contact, i.e., coupling other than inductive or capacitive coupling.
236. Conductivity - The measured ability of a conductor to
carry electricity.
237. Contention. A condition that occurs when more than one device
on a bus tries to access the bus at the same time. A condition when two or more
devices require access to a shared resource at the same time.
238. Contiguous. Two items placed one after another, next to each
other. Adjacent.
239. Continuity. An uninterrupted, complete path for current flow.
Reference
240. Contrast. The relation between the intensity of color,
brightness, or shading of an area occupied by a display element, display group,
or display image on the display surface of a display
241. Cosmic rays: Highly penetrating particle rays from outer space.
Primary cosmic rays that enter the Earth’s upper atmosphere consist mainly of
protons. Cosmic rays of low energy have their origin in the sun, those of high
energy in galactic or extragalactic space, possibly as a result of supernova
explosions. Collisions with atmospheric particles result in secondary cosmic
rays (particles) and secondary gamma rays (EM waves).
242. Co-tree : The complementary set of branches
of the tree is called co-tree.
243. coulomb - Unit of electric charge. A negative coulomb charge
consists of 6.24 × 1018 electrons.
244. Coulomb. A measure of the quantity of electricity. One coulomb
is equal to 6.28 x 10^18 electrons.
245. Counter - Counters are
elements counting the number of clock signals and outputting them as binary or
decimal representation on the output pins.
246. Coupling Loss. The loss that occurs when energy is
transferred from one circuit, circuit element, or medium to another.
247. Coupling Transformer. A transformer used to couple two
circuits together.
248. Crest Factor. The ratio of the peak value to rms value of a
periodically varying signal.
249. Critical Angle. The maximum angle at which radio waves can be
transmitted and still be refracted back to earth.
250. Critical Frequency. The maximum frequency at which a radio
wave can be transmitted vertically and still be refracted back to earth.
251. Crossover: A filter network which separates frequencies into
"bands" which match the capabilities of the loudspeaker drivers
within an enclosure.
252. Crystal Oscillator. [XO] An oscillator in which the frequency
is controlled by a piezoelectric crystal.
253. crystal - Natural or synthetic piezoelectric or semiconductor
material with atoms arranged with some degree of geometric regularity.
254. Crystal. A natural substance, such as quartz or tourmaline,
that is capable of producing a voltage when under physical stress or of
producing physical movement when a voltage is applied.
255. current feedback - Feedback configuration where a portion of
the output current is fed back to the amplifier input.
256. Current Regulator. A circuit that provides a constant current
output.
257. Current Standing-Wave Ratio. The ratio of maximum to minimum
current along a transmission line.
258. Current : It is rate of flow of electrons
in conductive or semi-conductive materials. Its units are amperes.
259. Cutoff Frequency: Normally defined as the frequency where the
output from a filter has fallen by 3dB from the maximum level obtainable
through the filter.
260. Cycle Life. Number of discharge-charge cycles that a battery
can tolerate under specified conditions before it fails to meet specified
criteria as to performance
261. Cycle. One complete positive and one complete negative alternation
of a current or voltage. A 360-degree rotation of a vector generating a sine
wave.
262. D.C Load Line : In CE amplifier Characteristics,
it is the straight line joining points Vce=Vcc on the voltage axis to the point
Vcc/Rc on the current axis, Rc being the resistor in the collector circuit.
263. Damped Wave. A sinusoidal wave in which the amplitude
steadily decreases with time. Often associated with energy loss.
264. Damping. The process of smoothing out oscillations. The
progressive decay with time in the amplitude of the free oscillations in a
circuit.
265. Data Bus. A bus used to transfer data within or to and from a
processing unit or storage device.
266. Data Communication. The transfer of information between
functional units by means of data transmission according to a protocol.
267. Data Compaction. The reduction of the number of data
elements, bandwidth, cost, and time for the generation, transmission, and
storage of data without loss of information by eliminating unnecessary
redundancy, removing irrelevancy, or using special coding.
268. Data Compression. Increasing the amount of data that can be
stored in a given domain, such as space, time, or frequency, or contained in a
given message length. Reducing the amount of storage space required to store a
given amount of data, or reducing the length of message required to transfer a
given amount of information.
269. Data Frame. A packet of transmitted information that contains
at a minimum, the destination address and information being transmitted.
Additional information also being transmitted may include the source address, a
check word or CRC, and frame length.
270. Data Integrity. The condition in which data are identically
maintained during any operation, such as transfer, storage, and retrieval.
271. Data Link. The means of connecting one location to another
for the purpose of transmitting and receiving data. The communication path
between nodes on a network.
272. Data logger - A device used to measure and record input from
sensors such as temperature or pressure
273. Data Processing. The execution of a systematic sequence of
operations performed upon data. Synonymous with information processing.
274. Data Signaling Rate. The aggregate rate at which data pass a point
in the transmission path of a data transmission system.
275. Data Stream. The data passing through a communication
channel, in a single operation.
276. Data Transfer Rate. The average number of bits, characters,
or blocks per unit time passing between corresponding equipment in a data
transmission system.
277. Data Transmission. The transfer of information from one place
to another or from one part of a system to another. The sending of data from
one place to another by means of signals over a channel.
278. database -A database is an application that
manages data and allows fast storage and retrieval of that data.
279. DBB-SC modulation : in this modulation we can
transmit the upper and lower sidebands only.
280. DC to DC Converter. A component or electronic circuit used to
convert DC voltages into other levels. A module that accepts one level of DC
voltage and outputs a different voltage level.
281. Dead Short. A short circuit having minimum resistance. A
direct connection between two points. The word Short could also refer the same
condition, and might be used in short hand.
282. Deadlock. A condition that exist when two processors or
systems sharing the same resource try to access that resource but prevent each
other from access.
283. Debugger - A program that allows the user to detect errors in
a program.
284. Debugging - The process of tracking and correcting errors
285. Decimal Converter. A circuit or function that converts
decimal to something else.
286. Decimal Counter. A counter that counts in decimal, between 0
and 9.
287. Decimal Digit. In decimal notation, one of the characters 0
through 9.
288. Decimal Point. The radix point in decimal representation.
289. Decimal to Binary Converter. A circuit used to convert from a
base 10 number to a base 2 number.
290. Decimal. Pertaining to the number representation system with
a radix of ten.
291. Deemphasis. In FM transmission, the process of restoring
(after detection) the amplitude-vs-frequency characteristics of the
signal.
292. Deflection Coil. In a cathode-ray tube, coils used to bend an
electron beam a desired amount.
293. Degeneration. The process whereby a part of the output signal
of an amplifying device is returned to its input circuit in such a manner that
it tends to cancel part of the input.
294. Delta Modulation. [DM] A form of Analog-to-digital signal
conversion, only an increase or decrease of the signal amplitude from the
previous sample is sent whereas a no-change condition causes the modulated
signal to remain at the same 0 or 1 state of the previous sample.
295. Delta-Sigma Modulation. Delta modulation in which the
integral of the input signal is encoded rather than the signal itself.
296. Demodulation : The process of separating message
signal from carrier signal is known as demodulation. It is inverse process of
modulation.
297. Demultiplexer (demux): A device used to separate two or more
signals that were previously combined by a compatible multiplexer and are
transmitted over a single channel.
298. depletion mode - In a FET, an operating mode where reverse
gate-source voltage is used to deplete the channel of free carriers. This
reduces the size of the channel and increases its resistance
299. Dielectric Field. The space between and around charged bodies
in which their influence is felt. Also called Electric Field of Force or an
Electrostatic Field.
300. Dielectric Heating. The heating of an insulating material by
a high-frequency electric field.
301. Dielectric Losses. The losses resulting from the heating
effect on the dielectric material between conductors.
302. Dielectric Withstanding Voltage. Maximum potential gradient
that a dielectric material can withstand without failure.
303. Difference Amplifier. An amplifier that amplifies the
difference between two inputs.
304. differential amplifier - An amplifier in which the output is
in proportion to the differences between voltages applied to its two inputs.
305. differentiator - A circuit in which the output voltage is in
proportion to the rate of change of the input voltage. A high pass RC circuit.
306. Differentiator. A circuit which has an output voltage
amplitude that is proportional to the derivative of the input voltage
307. Diffraction: Change in direction of propagating energy around an
object caused by interference between the radiated energy and induced currents
in the object.
308. Digital Signal Processing - A technique for the
processing of digital signals by various filter algorithms to obtain some
desired output.
309. Digital Signal Processor - A microprocessor optimized in
hardware design and software instruction set for the processing of analog
signals digitally. This is achieved by DFT and similar techniques.
310. Diode - An electronic part that restricts and directs
electrons (or electricity) to flow in only one direction.
311. Diode Compensation : It is the technique makes use of
temperature sensitive device such as diode in such a way as to introduce
compensating changes to stabilize the operating point.
312. Diode : Any two-electrode device that
conducts in only one direction.
313. DIP - Integrated circuit package having two rows of connecting
pins.
314. Direct coupled amplifier : It is a cascade amplifier without
coupling element use.
315. direct coupling - Where the output of an amplifier is
connected directly to the input of another amplifier or to a load.
316. Discharge (Battery) - The conversion of the chemical
energy of a cell or battery into electrical energy and withdrawal of the
electrical energy into a load.
317. Dish: An antenna system consisting of a parabolic shaped reflector
with a signal feed element at the focal point. Dish antennas commonly are used
for transmission and reception from microwave stations and communications
satellites.
318. dissipation - Release of electrical energy in the form of
heat.
319. distortion - An undesired change in a waveform or signal.
320. Distortion : the unwanted change in shape of
waveform.
321. Distortion: The difference between the wave shape of an original
signal and the signal after it has traversed a transmission circuit.
322. Distributed elements : These are the elements, which are
not separable for analytical purpose.
323. Distributive Law. In Boolean algebra the law which states
that if a group of terms connected by like operators contains the same
variable, the variable may be removed from the terms and associated with them
by the appropriate sign of operation for example, A(B + C) = AB + AC.
324. DLL - Dynamic Link Library. A file that is loaded by relevant
programs to access information needed to run the software. A single DLL file
can be shared by multiple relevant programs.
325. DNS - Domain Name System. The DNS is an international
network of Internet domain name servers, names, and addresses that enables
locating computers on the internet.
326. Domain Name System - The DNS is an international network of
Internet domain name servers, names, and addresses that enables locating
computers on the internet.
327. Doped semiconductor: A semiconductor that has had impurity atoms
added to modify the electrical conduction characteristics.
328. doping - The process of adding impurity atoms to intrinsic
(pure) silicon or germanium to improve the conductivity of the semiconductor
material.
329. Dot Matrix Printer - A printer that produces dots to form
characters. Dot matrix printers are still in use and mainly for character
output - meaning letters and numbers. They are not well suited for graphics or
high quality letters.
330. Double sideband suppressed carrier modulation: in this modulation we can transmit the upper
and lower sidebands only.
331. Download - To receive a file from a remote server.
332. dual in-line package - Integrated circuit package having two
rows of connecting pins.
333. dual trace oscilloscope - Oscilloscope that can
simultaneously display two signals.
334. Earphone. [Earbud] A transducer placed near the ear or over
the ear. A small speaker placed over one or both ears.
335. Echo. The reflection of the original sound wave as it bounces
off a distant surface.
336. Eddy Current Loss. Losses caused by random current flowing in
the core of a transformer. Power is lost in the form of heat.
337. Electric circuit : If a network contains at least
one closed path, it is called an electric circuit.
338. Electrical Network : Any inter connection of two or
more circuit elements it is called an electrical network.
339. Electrical Symbols. Graphic symbols used to illustrate the
various electrical or electronic components of a circuit.
340. Electrolyte (Battery) - In a lead-acid battery, the
electrolyte is sulfuric acid diluted with water. It is a conductor and also a
supplier of hydrogen and sulfate ions for the reaction.
341. electromagnetic communication - Use of an electromagnetic
wave to pass information between two points. Also called wireless
communication.
342. Electromagnetic Field. The combination of an electric (E)
field and a magnetic (H) field.
343. Electromagnetic interference : disturbance is affected to
circuit by the electromagnetic radiation generated by other source.
344. electromagnetic spectrum - List or diagram showing the range
of electromagnetic radiation.
345. electromagnetic wave - Wave that consists of both electric
and magnetic variation.
346. electromagnetism -Relates to the magnetic field generated
around a conductor when current is passed through it.
347. electromechanical transducer - Device that transforms
electrical energy into mechanical energy (electric motor) or mechanical energy
into electrical energy (generator).
348. electron flow -Electrical current produced by the movement of
free electrons towards a positive terminal.
349. Electron gun: An electron emission material that is heated to
produce the electron beam. Usually physically shaped and electrically
controlled to form a pencil lead sized beam.
350. electron - Smallest sub atomic particle of negative charge
that orbits the nucleus of an atom.
351. EMI : its full form is Electromagnetic
interference. Disturbance is affected to circuit by the electromagnetic
radiation generated by other source.
352. emitter follower - A common collector amplifier. Has a high
current gain, high input impedance and low output impedance
353. Energy : It is the capacity for doing
work. It may exist in many forms such as mechanical, chemical, electrical, and
etc. its units are joules.
354. EPROM -
Erasable PROM. EPROMs allow
the contents to be erased by exposing its builtin window to UV light. After
this process, all memory cells contain $ff and the EPROM can be written again.
355. Equalization. The process of compensating for distortion
within a circuit by adding additional networks that compensate for any gain
that was lost or increased over some frequency band.
356. Equalizer. A component or network that provides equalization
by correcting, or compensating for frequency related undesired amplitude
changes which have occurred within the system.
357. equivalent resistance - Total resistance of all the individual
resistances in a circuit.
358. Excitation Voltage. The supply voltage required to activate a
circuit.
359. Exciting Current. The current that flows in the primary
winding of a transformer when the secondary is open-circuited; it produces a
magnetic flux field. Also called magnetizing current.
360. Exclusive OR. A function whose output is a 1 if one and only
one of the input variables is a 1.
361. Exclusive-OR Gate. A gate that produces a logic 1 output when
the inputs are different, but not when they are the same.
362. Extension - A computer file term that refers to the three
letters after the dot in a file name.
363. Extract - This word basically means to "uncompress"
files of data. Files are sometimes "compressed" (compacted or zipped)
to make the file size smaller and thus easier to transfer over the internet.
Once received, the files are "extracted" to original size and
directory structure.
364. Extrinsic semiconductor: A semiconductor that has been doped with
impurities to modify the electrical conduction characteristics.
365. fall time - Time it takes the falling edge of a pulse to go
from 90% of peak voltage to 10% of peak voltage.
366. farad - The basic unit of capacitance.
367. Farad : It is the units for capacitor. It
is denoted by F.
368. Farad. The basic unit of capacitance. A capacitor has a
capacitance of 1 farad when a voltage potential of 1 volt across it produces a
charge of 1 coulomb.
369. Faraday Constant. The magnitude of electric charge per mole
of electrons; 96,485.3365 C mol-1.
370. feedback amplifier - An amplifier with an external signal path
from its output back to its input.
371. feedback - A portion of the output signal of any circuit
which is connected back to the input of the same circuit.
372. Feedback : It is the process of injecting a
fraction of output energy of same device back to the input.
373. Female Contact. A contact that accepts a mating contact by
having it inserted within the contact.
374. FET : It is a semiconductor device in
which the current is controlled by an electric field. It is a unipolar device.
Since current is carried by only majority carriers.
375. Fidelity : reproducing the sound or image
accurately
376. field effect transistor - (FET) A voltage controlled
transistor in which the source to drain conduction is controlled by gate to
source voltage.
377. Field Effect Transistor : It is a semiconductor device in
which the current is controlled by an electric field. It is a unipolar device.
Since current is carried by only majority carriers.
378. FIFO - First In First Out. Think of this as "first come
first serve basis". Storage devices using this setting will take
care of data in the order in which it was received.
379. filament - Thin thread of carbon or tungsten which produces
heat or light with the passage of current.
380. File Server. A high-capacity disk storage device or a
computer that each computer on a network can use or access and retrieve files
that can be shared among attached computers.
381. Film Resistor. A resistor whose resistive element is a thin
strip of conductive film deposited on a insulating core.
382. Film. Conductive or non-conductive material deposited on a
glass or ceramic substrate. Used for passive circuit components, resistors, and
capacitors.
383. filter - Network consisting of capacitors, resistors and/or
inductors used to pass certain frequencies and block others.
384. Filtering: a process used to remove or accentuate specific
frequencies or frequency ranges of a signal.
385. Fixed Bias : A CE transistor is said to
operate with fixed bias when d.c. base current IB is fixed.
386. Fixed resistor: A resistor that have a constant resistance,
independent of temperature, voltage, and other operating parameters.
387. Floppy - A term used for the older floppy disks that use
magnetism to store data on a round disk encased in a square plastic jacket.
Write protection is controlled by open or closed square notch in the upper
corner of the disk
388. Flux - A material that is used to assist in soldering
electronics parts by making the metals easier to join. Flux core solder has the
flux already in the center of the solder wire.
389. flux density - The concentration of magnetic lines of force.
Determines strength of the magnetic field.
390. flux - In magnetism, the magnetic field consisting of lines
of force.
391. FMFB demodulator : it is a FM demodulator with
negative feedback.
392. Form factor : In any wave, it is the ratio of
the rms value of the wave to the average value of the wave.
393. Forward Bias : Voltage applied to PN junction
with positive terminal to P-side and negative terminal to N-side.
394. Forward bias: A bias voltage applied to the PN junction of a diode
or transistor that makes the P-type side positive with respect to the N-type
side.
395. Forward current: The large current flow in a diode that results
from the application of a forward bias voltage.
396. Frequency demodulation : the process of recovering the
original signal from frequency modulated signal
397. Frequency modulation : The process of varying the
frequency of carrier signal with respect to message signal is known as
frequency modulation.
398. frequency multiplier - A harmonic conversion circuit in which
the frequency of the output signal is an exact multiple of the input frequency.
399. frequency response curve - A graph of amplitude over
frequency indicating a circuit response to different frequencies.
400. frequency response - Indication of how well a circuit
responds to different frequencies applied to it.
401. Frequency response : It is the graph drawn between
voltage gain and signal frequency of an amplifier.
402. Frequency shift keying (FSK): A signaling scheme whereby the
digital data modulates the frequency of a carrier.
403. frequency-division multiplex - (FDM) Transmission of two or
more signals over a common path by using a different frequency band for each
signal.
404. frequency-domain analysis - A method of representing a
waveform by plotting its amplitude against frequency.
405. Full Duplex - A data transmission method in which sending and
receiving of data occurs simultaneously.
406. full scale deflection - (FDS) Deflection of a meter's pointer
to the farthest position on the scale.
407. full wave rectifier - Rectifier that makes use of the full AC
wave in both the positive and negative half cycles.
408. Full Wave Rectifier : It is a circuit which converts
the a.c. voltage in to pulsating d.c. voltage using both half cycles of the
applied a.c. voltage.
409. function generator - Signal generator that can produce sine,
square, triangle and saw tooth output waveforms.
410. fundamental frequency - Lowest frequency in a complex
waveform.
411. fuse - A protective device in the current path that melts or
breaks when current exceeds a predetermined maximum value.
412. Fuse : An overcurrent protective device
with a circuit opening fusible part that is heated and severed by the passage
of overcurrent through it.
413. gamma rays - High frequency electromagnetic radiation from
radio active particles.
414. Gamma rays: Electromagnetic radiation of very high energy (greater
than 30 keV) emitted after nuclear reactions or by a radioactive atom when its
nucleus is left in an excited state after emission of alpha or beta particles.
415. ganged - Mechanical coupling of two or more capacitors,
switches, potentiometers, or any other adjustable components so that adjusting
one control will operate all.
416. generator - Device used to convert mechanical energy to
electrical energy
417. gigahertz. [GHz] 1 x 109Hz.
418. Gray code: A particular binary number representation in which only
one bit changes in going from one level to an adjacent level.
419. Ground Clutter. Unwanted echoes, from surrounding land
masses, that appear on a radar indicator.
420. GUI - Graphical User Interface. Pictures are used to access
information. DOS was not a GUI program, but Windows gave us the ability to
click on icons and menus rather than typing in text commands.
421. Guide wavelength: The distance over which the fields of
propagating modes repeat themselves in a waveguide.
422. gunn diode - A semiconductor diode that utilizes the Gunn
effect to produce microwave frequency oscillation or to amplify a microwave
frequency signal.
423. Half Duplex - A data transmission method in which sending and
receiving of data occurs but not at the same time.
424. half wave rectifier - A diode rectifier that converts AC to
pulsating DC by eliminating either the negative or the positive alternation of
each input AC cycle.
425. Half Wave Rectifier : It is a circuit which converts
the a.c. voltage in to pulsating d.c. voltage using only half cycles of the
applied a.c. voltage.
426. Hall Effect. An electric field that is produced when a
current carrying conductor is placed in a magnetic field whose direction is
perpendicular to both the direction of the current and the magnetic field.
427. Hamming Code. An error-detecting and error-correcting binary
code, used in data transmission that can detect all single- and double-bit
errors and correct all single-bit errors.
428. Hamming Weight. The number of non-zero symbols in a symbol
sequence.
429. Hard Copy. A physical print out.
430. Hard Disk. A flat, circular, rigid plate with a magnetizable
surface on one or both sides used to store data.
431. Hardware Interrupt. An interrupt signal received from a
component external to the processor operating on the interrupt.
432. Hartley Oscillator : The Hartley oscillator is an
electronic oscillator using two coils in series, parallel to a single
capacitor, forming the LC circuit that determines the frequency
433. Heat Sink Insulator. A component specifically designed to be
thermally conductive and electrically insulating.
434. Heat Sink. A metallic device that dissipates or radiates into
the surrounding air the heat that is generated from an integrated circuit or
other device.
435. Heat Spreader. A metal heat exchanger or heat sink used with
computer memory module DIMMs and other components to pull [spread] heat away
from memory ICs or devices.
436. Henry : It is the units for inductance.
It is denoted by H.
437. Hertz : A measurement of frequency. One
hertz is equal to one inverse second (1/s); that is, one cycle per second,
where a cycle is the duration between similar portions of a wave.
438. Hexadecimal System. Pertaining to the number system with a
radix of sixteen. It uses the ten digits of the decimal system and the first
six letters of the English alphabet.
439. High Fidelity. The process of reproducing sound nearly
identical to the original.
440. High Frequency. The band of frequencies from 3 megahertz to
30 megahertz.
441. high-pass filter - A tuned circuit designed to pass all
frequencies above a desnigated cut-off frequency. Frequencies below the cut-off
frequency are rejected or attenuated
442. Hole: An electron vacancy in a covalent bond between two atoms in
a semiconductor.
443. hologram - Three-dimensional picture created with a laser.
444. holography - The science dealing with three-dimensional
optical recording.
445. horizontally polarized wave - Electromagnetic wave that has
the electric field in the horizontal plane.
446. h-parameters - (hybrid parameters) Transistor specifications
that describe the component operating limits under specific circumstances.
447. Hub. A multi-port device that acts as a switch or repeater
connecting one incoming port to another. A device that accepts a signal from
one point and redistributes it to one or more points. A Hub may be wired or
wireless. A distribution point in a network.
448. Huffman code: A variable-length source code that optimally
represents lower probability samples with long code words and higher
probability samples with short code words so as to minimize overall average
codeword length.
449. Hydrometer - A float type instrument used to determine
the state-of-charge of a battery by measuring the specific gravity of the
battery electrolyte (i.e., the amount of sulfuric acid in the electrolyte).
450. Hydrometer: A testing device used to measure specific gravity,
particularly the specific gravity of the dilute sulphuric acid in a lead-acid
storage battery, to learn the state of charge of the battery.
451. Hygrometer: An instrument that measures the relative humidity of
the atmosphere.
452. Hygroscopic: The ability of a substance to absorb moisture from
the air.
453. IC voltage regulator - Three terminal device used to hold the
output voltage of a power supply constant over a wide range of load variations.
454. Ideal current source : It is a two terminal element in
which the current is completely independent of the voltage through its
terminals.
455. Ideal Voltage source : It is a two terminal element in
which the voltage is completely independent of the current through its
terminals.
456. Idempotent Law. In Boolean algebra, combining a quantity with
itself either by logical addition or logical multiplication will result in a
logical sum or product that is the equivalent of the quantity (for example, A +
A = A; A x A = A).
457. Identity Law. In Boolean algebra, the law which states that
any expression is equal to itself.
458. Impedance - Expresed in Ohms is the vector sum of all opposition
to the flow of current in a (typically AC) circuit which includes resistance, capacitance andinductance.
459. impedance matching - Matching the output impedance of a
source to the input impedance of a load to attain maximum power transfer.
460. in phase - When two or more waves of the same frequency have
their positive and negative peaks occurring at the same time.
461. Incandescent. The process of emitting light by being heated
to a high temperature, as in passing current through a wire until it heats up
462. Incident Wave. The wave that strikes the surface of a medium.
The wave that travels from the sending end to the receiving end of a
transmission line.
463. Indexed Address. An address that is altered by the content of
an index register.
464. Induced Current - Current in a conductor resulting from
a nearby electromagnetic field.
465. Induction losses. The losses that occur when the
electromagnetic field around a conductor cuts through nearby metallic objects
and induces a current into that object.
466. Inductive load. A load that contains a large amount of
inductance, or a load that is more inductive than capacitive or resistive.
467. Information bearing signal : The signal which is used for
carrying the information is called information bearing signal.
468. Information capacity : It can be defined as maximum rate
at which message signal can be transmitted across the channel without any
error.
469. Instantaneous sampling : the ideal form of sampling is
called instantaneous sampling.
470. insulated - When a non conducting material is used to isolate
conducting materials from one another.
471. insulating material - Material that will prevent the flow of
current due to its chemical composition.
473. Integrated Digital Network. [IDN] A network that uses both
digital transmission and digital switching.
474. integrated - When two or more components are combined into a
circuit and then incorporated into a single package.
475. integrator - A device that approximates and whose output is
proportional to an integral of the input signal. A low pass filter.
476. Integrator. A circuit that performs integration on the input
signal.
477. Interface - Any hardware or software that connects a computer
to another electronic or software system.
478. Interrupt. A suspension of a process, such as the execution
of a computer program, caused by an event external to that process, and
performed in such a way that the process can be resumed. A break in the normal
flow of a program, caused by an external signal that requires attention.
479. Intersection Law. In Boolean algebra, the law which states
that if one input to an AND gate is already TRUE, then the output will depend
upon the state of the other inputs only.
480. ISO - International Standards Organization. Organizations
that set the rules for different types of standards. Example - ISO 9001 is a
manufacturing quality standard. ISO 14001 is an environmental standard.
481. JFET. Junction Field Effect Transistor, a voltage controlled
transistor and not current controlled. A transistor in which the conduction is
due entirely to the flow of majority carriers through a conduction channel
controlled by an electric field arising from a voltage applied between the gate
and source terminals.
482. Joule. The work done by a force of one newton acting through
a distance of one meter.
483. Joules : it is units for energy.
484. JPEG - Joint Photo Experts Group. The most common type of
image or picture file format.
485. Junction : It is a point where three or more
elements meeting at point it is called Junction.
486. Karnaugh Map. A graphical method of representing a Boolean
function. A True Table displayed so that a circuit reduction can take place.
487. KCL : It states that the algebraic sum
the currents meeting at a point it is equal to zero. (or) It states that the
algebraic sum of currents entering into point is equal to the algebraic sum the
leaving currents at that point.
488. Kelvin scale : It is the scale which is used to
measure the temperature in Celsius scale and it pointed as zero while the
temperature is zero.
489. Kelvin. A unit of temperature.
490. Keyboard. A peripheral device used with a personal computer
which allows data entry.
491. Kilo. A prefix meaning one thousand, 103.
492. Kinetic Energy. Energy that a body possesses by virtue of its
motion.
493. Kirchhoff current law : It states that the algebraic sum
the currents meeting at a point it is equal to zero. (or) It states that the
algebraic sum of currents entering into point is equal to the algebraic sum the
leaving currents at that point.
494. Kirchhoff voltage law : It states that the algebraic sum
of voltages across each element is equal to zero. (Or) it states that the
algebraic sum of voltage drops in a mesh is equal to the algebraic sum of
voltage rises in that mesh.
495. Knee Voltage : In PN junction, it is the forward
voltage after which current starts to increase rapidly.
496. KVL : It states that the algebraic sum
the currents meeting at a point it is equal to zero. (or) It states that the
algebraic sum of currents entering into point is equal to the algebraic sum the
leaving currents at that point.
497. Laminate: A material consisting of layers of the same or different
materials bonded together and built up to the required thickness.
498. Latch - A set
of flip-flops with a
common clock signal. In each cycle, they take the logical input signals over to
their outputs. Usually used to form multiplexaddress busses. As opposed
to flip-flops, latches are
level-triggered.
499. LED - An LED (Light Emitting Diode) is a diode emitting
light when operated in a forward direction. Since it is a diode, it has a
nearly negligible resistance.
500. Lenz's law - The current induced in a circuit due to a change
in the magnetic field is so directed as to oppose the flux, or to exert a
mechanical force to oppose the motion.
501. level detector - An op-amp circuit that compares two inputs
and provides a DC output indicating the polarity relationship between the
inputs.
502. lie detector - Piece of electronic equipment also called a
polygraph used to determine whether a person is telling the truth by looking
for dramatic changes in blood pressure, body temperature, breathing rate, heart
rate and skin moisture in response to questions.
503. lifetime - The time from the creation of an electron hole
pair until recombination occurs.
504. light - Electromagnetic radiation in a band of frequencies
that can be received by the human eye.
505. light-emitting diode - A semiconductor diode that converts
electric energy into electromagnetic radiation at a visible and near infrared
frequencies when its pn junction is forward biased.
506. Limiter - a nonlinear
electronic circuit whose output is limited in amplitude; used to limit the
instantaneous amplitude of a waveform.
507. line regulation - The ability of a voltage regulator to
maintain a constant voltage when the regulator input voltage varies.
508. Linear elements : The element which is having
voltage-current characteristics is at all times a straight line through the
origin. Resistor is the example for these elements.
509. linear scale - A scale in which the divisions are uniformly
spaced.
510. Linearity. A change in the input which produces a directly
proportional change in an output.
511. Links : The branches of co-tree are
called links.
512. Liquid Crystal Display. [LCD] A display device that creates
characters by means of the action of electrical signals on a matrix of liquid
cells that become opaque when energized
513. Lithium-Ion Battery. A Battery that uses lithium metallic
oxide in its positive electrode (cathode) and carbon material in its negative
electrode (anode).
514. load current - Current drawn from a source by a load.
515. load impedance - Vector sum of reactance and resistance in a
load.
516. load regulation - The ability of a voltage regulator to
maintain a constant output voltage under varying load currents.
517. load resistance - Resistance of a load.
518. Load - The amount of electrical power required by connected
electrical equipment. / The total impedance of all the items in the output
circuit.
519. Local Area Network. [LAN] A network which only operates or
spans a small area, although there is no strict size to the operational area. A
network which only operates within a particular building.
520. Loop Gain. The sum of the gains, expressed in dB, acting on a
signal passing around a closed path.
521. Loop : It is the group of elements or
branches to form a closed path is called Loop.
522. Low Frequency Distortion. Frequency distortion which effects
lower frequencies.
523. Low Frequency. The band of frequencies from 30 kHz to 300
kHz.
524. low pass filter - A tuned circuit designed to pass all
frequencies below a designated cut-off frequency.
525. Lumen - Standard unit of measure for light energy.
526. Lumped Elements : The elements which are very small
in size and in which simultaneous action actions takes place for any given
cause at the same instant of time. Capacitor, resistors, inductors,
transformers are examples for this elements.
527. Lux - The SI unit of luminance. One lux is one lumen per
square meter.
528. magnet - Body that can be used to attract or repel magnetic
materials.
529. magnetic field - Magnetic lines of force traveling from the
north pole to the south pole of a magnet.
530. magnetic flux - The magnetic lines of force produced by a
magnet.
531. magnetic poles - Points of a magnet from which magnetic lines
of force leave (north pole) and arrive (south pole).
532. magnetism - Property of some materials to attract or repel
others.
533. Magnetism. The property possessed by certain materials by
which these materials can exert mechanical force on neighboring masses of
magnetic materials and can cause currents to be induced in conducting bodies
moving relative to the magnetized bodies.
534. magnetizing force - Also called magnetic field strength. It
is the magneto motive force per unit length at any given point in a magnetic
circuit.
535. magneto motive force - Force that produces a magnetic field.
536. Main Lobe. Of an antenna radiation pattern, the lobe
containing the maximum power.
537. Majority carriers: In a semiconductor, the type of charge carrier
with the larger population. For example, in an N-type semiconductor, electrons
are the majority carriers.
538. Master-Slave Timing. Timing in which one station or node
supplies the timing reference for all other interconnected stations or nodes.
539. matched impedance - Condition that occurs when the output
impedance of a source is equal to the input impedance of a load.
540. matching - Connection of two components or circuits so that
maximum power is transferred between the two.
541. maximum power transfer - A theorem that states that maximum
power will be transferred from source to load when input impedance of the load
equals the output impedance of the source.
542. Maxwell - Unit of magnetic flux. One maxwell equals one
magnetic line of force.
543. MBPS - Mega Bytes Per Second. Used to measure data transfer
speed.
544. Medium Frequency. The band of frequencies from 300 kHz to 3
MHz.
545. Mega. A prefix meaning one million, 106
546. Megohmmeter - A testing device that applies a DC voltage
and measures the resistance (in millions of ohms) offered by conductor's or
equipment insulation.
547. Mesh : It is a loop which can’t contain
any other inner loops called Mesh.
548. metal film resistor - A resistor in which a film of metal
oxide or alloy is deposited on an insulating substrate
549. Metal Film Resistor. A resistor that uses a thin film of
metal alloy as the resistive element.
550. Metal Oxide Varistor. A resistor that changes value with applied
voltage. A varistor may also be called a Voltage Dependent Resistor. Varistors
will have a negative voltage coefficient.
551. mica capacitor - Capacitor using mica as the dielectric.
552. Micro. A prefix meaning one-millionth, 10-6.
554. microphone - Electro acoustic transducer that converts sound
energy into electric energy.
555. Microphone. An energy converter that changes sound energy
into electrical energy.
556. microwave - Band of very short wavelength radio waves within
the UHF, SHF and EHF bands.
557. Miller's theorem - A theorem that allows you to represent a
feedback capacitor as equivalent input and output shunt capacitors.
558. Minor Lobe. The lobe in which the radiation intensity is less
than that of a major lobe
559. Minority Carriers. Either electrons or holes, whichever is
the less dominant carrier in a semiconductor device. In P-type semiconductors,
electrons are the minority carriers; in N-type semiconductors, the holes are
the minority carriers.
560. Minority carriers: In a semiconductor, the type of charge carrier
with the smaller population. For example, in an N-type semiconductor, holes are
the minority carriers.
561. Minority Current. A very small current that passes through
the base-to-collector junction when this junction is reverse biased.
562. Mismatch. A combination when the load impedance does not
match the source impedance.
563. Mixer: A circuit used to combine two or more signals to produce a
third signal that is a function of the input waveforms.
564. Modem. A circuit or device that performs both modulation and
Demodulation.
565. Modulation Index. The ratio of frequency deviation to the
frequency of the modulating signal.
566. Modulation : The process of combining message
signal and carrier signal to Carrie the message signal to destination point
567. monostable multivibrator - A multivibrator with one stable
output state. When triggered, the circuit output will switch to the unstable
state for a predetermined period of time and then return to the stable state
568. Monostable Multivibrator. A multivibrator that has one steady
state. A signal (trigger) must be applied to cause change of states.
569. Monostable. A circuit or component that has one stable state
and one quasi-stable state. A one-shot. A circuit that takes one stable state
until it receives a trigger pulse, and than moves to a quasi-stable state.
570. Motor : A machine which converts
electrical power into mechanical power.
571. Motor. A machine that converts electrical energy to
mechanical energy.
572. multi segmant display - Device made of several light emitting
diodes arranged in a numeric or alphanumeric pattern. By lighting selected
segments numeric or alphabet characters can be displayed.
573. Multi-meter - An
all-in-one measuring device. It combines a volt-meter, an amp-meter and
an ohm-meter which
usually also can act as continuity tester. Often it contains a transistor tester. There are both analog and
digital types.
574. Multiple access : it is a technique whereby many
users can share the communication channel at a time.
575. mutual inductance - Ability of one inductor's lines of force
to link with another inductor.
576. Mutual Inductance. A circuit property existing when the
relative position of two inductors causes the magnetic lines of force from one
to link with the turns of the other. The symbol for mutual inductance is M.
577. NAND. A logic function of A and B that is true if either A or
B or both are false.
578. Narrowband noise : The noise produced at the output
side of narrowband filter is called narrowband noise.
579. negative charge - A charge that has more electrons than protons
580. negative feedback - A feedback signal 180° out of phase with
an amplifier input signal. Used to increase amplifier stability, bandwidth and
input impedance. Also reduces distortion.
581. Negative Feedback : The feedback voltage or current
is in out of phase with the input signal and thus opposed it is known as
negative feedback.
582. negative ion - An atom having a greater number of electrons
in orbit than there are protons in the nucleus.
583. Negative Resistance Regions : It is the region on the UJT
characteristic wave where the device does not obeys OHMs law. That means the
voltage is inversely proportional to current.
584. negative resistance - A resistance such that when the current
through it increases the voltage drop across the resistance decreases.
585. negative temperature coefficient - A term used to describe a
component whose resistance or capacitance decreases when temperature increases.
586. Negative-Resistance Element. A component having an operating
region in which an increase in the applied voltage increases the resistance and
produces a proportional decrease in current. Examples include tunnel diodes and
silicon uni junction transistors.
587. Negative-Resistance. A component that has a current-voltage
characteristic with a negative slope; the current decreases with increasing
voltage.
588. neon bulb - Glass envelope filled with neon gas which when
ionized by an applied voltage will glow red.
589. Netlist: A file of component connections generated from a
schematic. The file lists net names and the pins, which are a part of each net in
the design.
590. neutral atom - An atom in which the number of negative
charges (electrons in orbit) is equal to the number of positive charges
(protons in the nucleus).
591. neutral - A terminal, point or object with balanced charges.
Neither positive or negative.
592. Newton's Second Law of Motion. If an unbalanced outside force
acts on a body, the resulting acceleration is directly proportional to the
magnitude of the force, is in the direction of the force, and is inversely
proportional to the mass of the body.
593. Nibble. Four consecutive bits, or half of a byte.
594. Node : It is a point where two or more
elements meeting at point it is called Node.
595. Noise Limiter. Circuit that clips the peaks of the noise
spikes in a receiver.
596. Noise : It is the unwanted signal which
can degrade the signal or data.
597. No-Load Condition. The condition that exists when an
electrical source or secondary of a transformer is operated without an
electrical load.
598. Nomograph. An alignment chart that solves equations
graphically.
599. Non-conductor. An insulator. A material that does not conduct
current.
600. Non-Inductive load. A load that only contains resistive and or
capacitive elements.
601. Nonlinear elements : The element which does not have
“voltage-current characteristics are at all times a straight line through the
origin”.
602. Nonlinear resistor: A resistor with a value that depends strongly
on some external parameter such as temperature or voltage.
603. non-linear scale - A scale in which the divisions are not
equally spaced.
604. NOR. A logic function of A and B that is true if both A and B
are false.
605. north pole - Pole of a magnet out of which magnetic lines of
force are assumed to originate.
606. Norton’s Theorem : It states that any two terminal
liner network having a number of voltage or current sources and resistances can
be replaced by a simple equivalent circuit containing of a single current
source in parallel with a resistance.
607. Norton's theorem - Any network of voltage sources and
resistors can be replace by a single current source in parallel with a single
resistor.
608. NOT Circuit. A binary circuit with a single output that is
always the opposite of the input. Also called an Inverter Circuit.
609. notch filter - A filter which blocks a narrow band of
frequencies and passes all frequencies above and below the band.
610. npn transistor - A bipolar junction transistor in which a
p-type base element is sandwiched between an n-type emitter and an n-type
collector.
611. NPN Transistor : It is a transistor made of
sandwich of central P region and two outer N regions.
612. N-type semiconductor: A semiconductor that has been doped with
donor impurities to produce the condition that the population of free electrons
is greater than the population of holes.
613. nucleus - Core of an atom. The nucleus contains both positive
(protons) and neutral (neutrons) subatomic particles.
615. Ohmmeter : An instrument for measuring
resistance in ohms.
616. Ohms law : it states that “the current
passing through a conductor is directly proportional to the difference applied
across it, keeping temperature constant”.
617. Operating Point : The zero signal values of Ic and
Vce are known as operating point. It is the point of intersection of d.c. load
line with its characteristics for current IB.
618. Optical Coupler. A coupler composed of an LED [light source]
and a photodiode [light detector] contained in a light-conducting medium, all
in a single package.
619. Optical Detector. A transducer that generates an output
signal when irradiated with optical energy.
620. Optical Repeater. In an optical communication system, an
optoelectronic device or module that receives an optical signal, amplifies it
and retransmits it as an optical signal.
621. OR Gate. A gate that performs the logic OR function. It
produces an output 1 whenever any or all of its inputs is/are 1.
622. Oscillator : An electronic device that
generates alternating-current power at a frequency determined by the valuer of
certain constants in its circuits.
623. oscilloscope - An instrument used to display a signal
graphically. Shows signal amplitude, period and wave shape in addition to any
DC voltage present. A multiple trace oscilloscope can show two or more
waveforms at the same time for phase comparison and timing measurements.
624. out of phase - When the maximum and minimum points of two or
more waveshapes do not occur at the same time.
625. output impedance - Impedance measured across the output
terminals of a device without a load connected.
626. output power - Amount of power a component, circuit or system
can deliver to a load.
627. overload protection - Protective device such as a fuse or
circuit breaker that automatically disconnects a load when current exceeds a
predetermined value.
628. overload - Condition that occurs when the load is greater
than the system was designed to handle. (Load resistance too small, load
current too high.) Overload results in waveform distortion and/or overheating.
629. Packet Format. The structure of data, address, and control
information in a packet.
630. Packet. A sequence of binary digits, including data and
control signals, that is transmitted and switched as a composite whole, for
data communications.
631. PAM : its full form is pulse amplitude
modulation. in this modulation we can vary the amplitude of pulse with respect
to message signal call pulse amplitude modulation.
632. paper capacitor - Fixed capacitor using oiled or waxed paper
as a dielectric.
633. Parabolic Reflector. A paraboloid shaped reflector used in
both the RF and Microwave frequencies.
634. parallel - Circuit having two or more paths for current flow.
Also called shunt.
635. Parallel-to-Serial Converter. A component or circuit that
receives parallel data and outputs serial data.
636. Paraphase Amplifier. An amplifier that outputs two out of
phase signals based on a single input.
637. Parity bit : the error detection bit is call
parity bit
638. Parity Check. The process of checking the accuracy of binary
data, by counting the total number of 1s, or 0s, to insure that there is always
an odd or always an even amount depending on the parity.
639. Passive elements : These are the elements which are
capable of receiving power only. Examples for these are resistor, capacitor,
and inductor.
640. passive filter - A filter that contains only passive or non
amplifying components.
641. Path Loss. The attenuation undergone by a signal between a
transmitter and a receiver.
642. PDM : Its full form is Pulse duration
modulation. In this process we can vary the duration of the pulses with respect
to the message signal.
643. Peak Amplitude. The maximum value above or below a reference
line.
644. Peak Current. The maximum current that flows during a
complete cycle.
645. Peak factor : In any wave, it is the ratio of
the peak value of the wave to the rms value of the wave.
646. Peak Factor. The ratio of the peak value to rms value of a
periodically varying signal.
647. peak inverse voltage - (PIV) The maximum rated value of a AC
voltage acting in the direction opposite to that in which a device is designed
to pass current.
648. Peak Inverse Voltage : This is the maximum value of the
reverse voltage which the rectifier has to withstand during non conduction
period.
649. Peak Inverse Voltage. The maximum voltage applied in reverse
direction with-out damage to the semiconductor.
650. Peak to Peak value : In any sine wave, it is value
from the maximum value of the wave during positive half cycle to maximum value
of wave in negative half cycle.
651. peak to peak - Difference between the maximum positive and
maximum negative values of an AC waveform.
652. Peak value : In any sine wave, it is the
maximum value of the wave during positive half cycle, or maximum value of wave
in negative half cycle.
653. Peak Value. The maximum instantaneous value of a varying
current, voltage, or power.
654. peak - Maximum or highest amplitude level.
655. Perfboard. A Printed Wiring Board having pre-drilled holes at
distances of 0.1 inches square which will accept standard through-hole ICs and
other components. The drilled holes normally have copper pads for soldering the
components on one side of the board.
656. phase angle - Phase difference between two or more waves,
normally expressed in degrees.
657. Phase Detector. A circuit or instrument that detects the
difference in phase between corresponding points on two signals.
658. Phase Deviation. In phase modulation, the maximum difference
between the instantaneous phase angle of the modulated wave and the phase angle
of the unmodulated carrier.
659. Phase Inversion. Introduction of a phase difference of 180
degrees.
660. Phase Inverter. A circuit or component that outputs a signal
that is 180 degrees out of phase with the input.
661. phase shift - Change in phase of a wave form between two
points, expressed as degrees of lead or lag.
662. phase - Angular relationship between two waves.
663. Phase-Shift Oscillator. A circuit that oscillates by
providing feedback of 180 degree phase shift of the signal back to the input. The
example uses RC networks to shift the phase 60 degrees, per network and a PNP
transistor as the amplifier and to shift the signal another 180 degrees to
provide regenerative feedback. The value of the resistors and capacitors should
be selected to provide a 60 degree phase shift at the frequency of interest.
664. phonograph - Piece of equipment used to reproduce sound
stored on a disk called a phonograph record.
665. Photo diode - Diode which is
controlled by light. / it is a type of photodetector capable
of converting light into either current or voltage, depending
upon the mode of operation.
666. Photo transistor - Transistor which is
controlled by light. / a junction transistor, whose base signal is generated by
illumination of the base. The emitter current, and hence collector current,
increases with the intensity of the light
667. photoconduction - A process by which the conductance of a
material is change by incident electromagnetic radiation in the visible light
spectrum.
668. photoconductive cell - Material whose resistance decreases or
conductance increases when exposed to light.
669. Photoetching. Chemical process of removing unwanted material
in producing printed circuit boards.
670. photometer - Meter used to measure light intensity.
671. photoresistor - Also known as a photoconductive cell or light
dependent resistor. (LDR) A device whose resistance decreases with exposure to
light.
672. photovoltaic cell - Component commonly called a solar cell
used to convert light energy into electrical energy.
673. pinch-off region - A region on the characteristic curve of a
FET in which the gate bias causes the depletion region to extend completely
across the channel.
674. PIV : This is the maximum value of the
reverse voltage which the rectifier has to withstand during non conduction
period.
675. Pixel Count - The number of pixels that make up an image.
676. Pixel - Abbreviated term for Picture Element. This term
refers to the single dots of light that compose a image or picture.
677. Planner Graph : A graph is said to be planar if
it can be drawn on a plane surface such that no two branches cross each other.
678. Plasma: A gas that has been ionized to produce a conducting
medium.
679. plastic film capacitor - Capacitor in which alternate layers
of aluminum foil are separated by thin films of plastic dielectric.
680. Platter. The circular disk inside a Hard Disk Drive which holds
the magnetic data.
681. PN Junction : When a P-type semiconductor is
suitably joined to N-type semiconductor the contact surface is called PN
Junction.
682. PNP Transistor : It is a transistor made of
sandwich of central N region and two outer P regions.
683. Point to point communication : Transmitting signal between
single transmitter and single receiver known as point to point
communication.
684. polarity - Term used to describe positive and negative
charges.
685. positive charge - A charge that exists in a body that has
fewer electrons than protons.
686. positive feedback - A feedback signal that is in phase with
an amplifier input signal. Positive feedback is necessary for oscillation to occur.
687. Positive Feedback : The feedback voltage or current
is in phase with the input signal and thus adds it is known as positive
feedback.
688. Positive Feedback. Feedback in which the feedback signal is
in phase with the input signal.
689. positive ground - A system whereby the positive terminal of
the source is connected to the system's conducting chassis.
690. positive ion - Atom that has lost one or more valence
electrons resulting in a net positive charge.
691. Positive Temperature Coefficient. The characteristic of a conductor
in which the resistance increases as temperature increases.
692. potential difference - Voltage difference between two points
which will cause current to flow in a closed circuit.
693. Potential Difference : The difference in potential
energy of the chargers is called potential difference. Its units are volts.
694. Potentiometer - A
variable resistor the value
of which is determined by the position of a slider or a knob.
695. Power factor: Defined as the cosine of the angle between the
voltage across and the current through the load.
696. Power : It is the rate of change of
energy. It is measured in watts.
697. PPM : Its full form is Pulse position
modulation. In this process we can vary the position of the pulses with respect
to the message signal.
698. Principle Node : It is a point where three or more
elements meeting at point it is called Principle Node.
699. Product modulator : which can multiplies the message
signal with carrier wave.
700. Program - A set of computer instructions to perform a
specific task.
701. propagation delay - Time required for a signal to pass
through a device or circuit.
702. propagation time - Time required for a wave to travel between
two points.
703. Protocol - A set of rules and procedures that controls communications
between 2 or more devices.
704. proton - Sub atomic particle within the nucleus of an atom.
Has a positive charge.
705. P-type semiconductor: A semiconductor that has been doped with
acceptor impurities to produce the condition that the population of holes is
greater than the population of free electrons.
706. Pulsating DC. A DC voltage that varies in amplitude. A
current that flows in one direction but varies in intensity.
707. Pulse amplitude modulation : in this modulation we can vary
the amplitude of pulse with respect to message signal call pulse amplitude
modulation.
708. Pulse Duration Modulation. Pulse modulation in which the time
duration of the pulses is changed by the modulating signal.
709. Pulse duration modulation: In
this process we can vary the duration of the pulses with respect to the message
signal.
710. pulse fall time - Time for a pulse to decrease from 90% of
its peak value to 10% of its peak value.
711. Pulse position modulation : In this process we can vary the
position of the pulses with respect to the message signal.
712. pulse repetition frequency - The number of times per second
that a pulse is transmitted. Pulse rate.
713. pulse repetition time - Time interval between the start of
two consecutive pulses.
714. pulse rise time - Time required for a pulse to increase from
10% of its peak value to 90% of its peak value.
715. Pulse Width Modulation. Pulse modulation in which the duration of
the pulses is varied by the modulating voltage.
716. pulse - Rise and fall of some quantity (usually voltage) for
a period of time.
717. Pulse-Position Modulation. Pulse modulation in which the position
of the pulses is varied by the modulating voltage.
718. Pulse-Repetition Frequency. The rate, in pulses per second, at
which the pulses occur.
719. Pulse-Repetition Time. Interval between the start of one pulse and
the start of the next pulse.
720. Q-Meter. A device used to measure the Quality factor [Q] of a
circuit.
721. Quadrature Amplitude Modulation. Quadrature modulation in
which the two carriers are amplitude modulated.
722. Quantization Level. In the quantization process, the discrete
value assigned to a particular subrange of the analog signal being quantized.
723. Quantization noise: This is a type of noise that occurs when an
analog signal is converted into digital form by measuring and encoding the
range of analog input signal values as a set of numbers, usually in the binary
system, for manipulation in digital circuits, possibly followed by reconversion
to analog form.
724. Quantization. A process in which the continuous range of
values of an analog signal is sampled and divided into non-overlapping
subranges, and a discrete, unique value is assigned to each subrange.
725. radar - Acronym for "radio detection and ranging" A
system that measures the distance and direction of objects.
726. radio broadcast - Transmission of music, voice and other
information on radio carrier waves that can be received by the general public.
727. radio communication - Term used to describe the transfer of
information between two or more points by use of radio or electromagnetic
waves.
728. Radio frequency interference : disturbance is affected to
circuit by the electromagnetic radiation generated by other source.
729. radio-frequency amplifier - Amplifier having one or more
active devices to amplify radio signals.
730. radio-frequency generator - Generator capable of supplying RF
energy at any desired frequency in the radio-frequency spectrum.
731. RC coupled Amplifier : It is a cascade amplifier using a
resistor as load impedance and a capacitor as the coupling element.
732. real number - Number having no imaginary part.
733. receiver - Unit or piece of equipment used to receive
information.
734. Receiver : it is a device which can receive
the data from medium or channel.
735. Regulated Power Supplies : these are the D.C. power supplies
whose output voltage remains constant irrespective of variations of input
supply or load current.
736. Regulator - A device that is used to control the voltage
of a circuit by raising and lowering it.
737. Regulator: An electronic device that attempts to keep the output
signal constant in spite of changes in the other system characteristics.
738. relay - Electromechanical device that opens or closes
contacts when a current is passed through a coil.
739. Repeater - A network device that increases the signal to
allow data to be transmitted over longer cable distances.
740. Resistance : It is the property of material to
restrict the flow of electrons. It is denoted by ‘R’.
741. resistor color code - Coding system of colored stripes on a
resistor to indicate the resistor's value and tolerance.
742. Resolution - This is a measurement of the number of dots
displayed on a pc monitor
743. Reverse Bias : Voltage applied to PN junction
with positive terminal to N-side and negative terminal to P-side.
744. Reverse bias: A bias voltage applied to the PN junction of a diode
or transistor that makes the P-type side negative with respect to the N-type
side.
745. reverse breakdown voltage - Amount of reverse bias that will
cause a PN junction to break down and conduct in the reverse direction.
746. reverse current - Current through a diode when reverse
biased. An extremely small current also referred to as leakage.
747. Reverse current: The small current flow in a diode that results
from the application of a reverse bias voltage.
748. RFI : its full form is Radio frequency
interference. Disturbance is affected to circuit by the electromagnetic
radiation generated by other source.
749. RFID - Radio Frequency Identification tags are part of a
tracking system that uses intelligent bar codes to track items in a store
750. rheostat - Two terminal variable resistor used to control
current.
752. RPS : these are the D.C. power supplies
whose output voltage remains constant irrespective of variations of input
supply or load current.
753. sawtooth wave - Repeating waveform that rises from zero to
maximum value linearly drops back to zero and repeats. A ramp waveform.
754. Schematic - A drawing or diagram of an electrical circuit.
755. Schematic: A drawing or set of drawings that shows an electrical
circuit design.
756. Schottky diode - High speed diode that has very little
junction capacitance. Also known as a "hot-carrier diode" or a
"surface-barrier diode."
757. SDRAM - Synchonous DRAM. Differs from conventional DRAM in that it
internally gates (synchronises) all access using a single clock rather than
separate column and row clocks (driven by CAS & RAS)
758. Sensistor Compensation : It is the technique makes use of
temperature sensitive device such as sensistor in such a way as to introduce
compensating changes to stabilize the operating point.
759. Sequential logic: A logic circuit with memory.
760. series circuit - Circuit in which the components are
connected end to end so that current has only one path to follow through the
circuit.
761. series parallel network - Network that contains components
connected in both series and parallel.
762. seven segment display - Device made of several light emitting
diodes arranged in a numeric or alphanumeric pattern. By lighting selected
segments numeric or alphabet characters can be displayed.
763. short circuit - Also called a short. Low resistance
connection between two points in a circuit typically causing excessive current.
764. shunt resistor - Resistor connected in parallel or in shunt
with another component or circuit.
765. signal to noise ratio - Ratio of the magnitude of the signal
to the magnitude of noise usually expressed in decibels.
766. signal - Electrical quantity that conveys information.
767. silicon transistor - A bipolar junction transistor using
silicon as the semi conducting material.
768. silicon - (Si) Non metallic element (atomic number 14) used
in pure form as a semiconductor.
769. silicon-controlled rectifier - (SCR) Three terminal active
device that acts as a gated diode. The gate terminal is used to turn the device
on allowing current to pass from cathode to anode.
770. Simplex - A communications system in which data can only
travel in one direction.
771. single in-line package - Package containing several
electronic components (generally resistors) with a single row of connecting pins.
772. Single sideband modulation: In
this modulation we can transmit either upper sideband or lower sideband only.
773. SIP - Package containing several electronic components (generally
resistors) with a single row of connecting pins.
774. Source code word : In digital communication the
source encoder removes the redundant information from message signal. Then
resultant sequence of symbols is called source code word.
775. speaker - Transducer
that converts electrical energy into mechanical energy at audio frequencies
776. SSB modulation : In
this modulation we can transmit either upper sideband or lower sideband only.
777. Stability Factor : In CE amplifier, it is the rate
of change of collector current Ic with respect to collector leakage current
IC0, at constant β and VBE.
778. Stability - The ability of a device to maintain its
performance characteristics over a specified period of time.
779. Stabilization : The process of making operating
point independent of temperature change or variations in transistor parameters
is known as stabilization.
780. Star network : The passive three terminal
network consisting of three impedances Z1, Z2, Z3 is said to form a Star or T
Network.
781. State: The condition in which a system exists.
782. step-down transformer - Transformer in which the output AC
voltage is less than the input AC voltage.
783. step-up transformer - Transformer in which the output AC
voltage is greater than the input AC voltage.
784. Stereo multiplexing : it is the form of frequency
division multiplexing design to transmit two separate signals with same carrier.
785. stereo sound - System in which reproduced sound is delivered
through two or more channels to give a sense of direction to the source.
786. stop band - Range of frequencies outside the pass band of a
tuned amplifier.
787. superposition theorem - Theorem designed to simplify networks
containing two or more sources. It states that in a network containing more
than one source, the current at any one point is equal to the algebraic sum of
the currents produced by each source acting separately.
788. Superposition theorem : It states that in any liner
network containing two or more sources, the response in any element is equal to
the algebraic sum of the responses caused by individual sources acting alone,
while the other sources are non operative.
789. sweep generator - Test instrument designed to produce a
voltage that continuously varies in frequency over a band of frequencies. Used
as a source to display frequency response of a circuit on an oscilloscope.
790. switch - Electrical device having two states, on (closed) or
off (open). Ideally having zero impedance when closed and infinite impedance
when open.
791. T Network : The passive three terminal
network consisting of three impedances Z1, Z2, Z3 is said to form a Star or T
Network.
792. tank circuit - Parallel resonant circuit containing only a
coil and a capacitor. Both the coil and capacitor store electrical energy for
part of each cycle.
793. tantalum capacitor - Electrolytic capacitor having a tantalum
foil anode. Able to have a large capacity in a small package.
794. telegraphy - Communication between two points by sending and
receiving a series of current pulses either through wire or by radio.
795. telemetry - Transmission of instrument readings to a remote
location either by wire or by radio.
796. telephone line - Wires existing between subscribers and
central stations in a telephone system.
797. telephone - Apparatus designed to convert sound waves into
electrical waves which are sent to and reproduced data distant point.
798. telephony - Telecommunications system involving the transmission
of speech information, allowing two or more persons to communicate verbally.
799. teletypewriter - Electric typewriter that like a tele-printer
can produce coded signals corresponding to the keys pressed or print characters
corresponding to the coded signals received.
800. television - System that converts both audio and visual
information into corresponding electrical signals which are then transmitted
through wires or by radio waves to a receiver which reproduces the original
information.
801. tera - (T) Metric prefix that represents 1012.
802. terminal - Point at which electrical connections are made.
803. tesla - (T) Unit of magnetic flux density. (1 tesla = 1
Wb/m2).
804. thermal runaway - Problem that can develop in an amplifier
when an increase in temperature causes an increase in collector current. The
increase in collector current causes a further increase in temperature and so
on. Unless the circuit is designed to prevent this condition, the device can be
driven into saturation.
805. Thermal Runaway : in CE amplifier, self heating
results from power dissipation at the collector junction. This dissipation
causes rise in junction temperature which, in turn, increases ICo which rise in
Ic, in certain cases, result in increased power dissipation at collector
junction. This cumulative process is called thermal runaway.
806. thermal stability - The ability of a circuit to maintain
stable characteristics in spite of increased temperature.
807. Thermistor - A resistor that regulates an electrical circuit
based upon temperature.
808. Thermistor Compensation : It is the technique makes use of
temperature sensitive device such as thermistor in such a way as to introduce
compensating changes to stabilize the operating point.
809. thermistor - Temperature sensitive semiconductor that has a
negative temperature coefficient of resistance. As temperature increases,
resistance decreases.
810. thermocouple - Temperature transducer consisting of two
dissimilar metals welded together at one end to form a junction that when
heated will generate a voltage.
811. thermometry - Relating to the measuring of temperature.
812. thermostat - Device that opens or closes a circuit in
response to changes in temperature.
813. Thevenin's theorem - Theorem that replaces any complex
network with a single voltage source in series with a single resistance.
814. Thevenins Theorem : It states that any two terminal
liner network having a number of voltage or current sources and resistances can
be replaced by a simple equivalent circuit containing of a single voltage
source in series with a resistance.
815. thick film resistor - Fixed value resistor consisting of
thick-film resistive element made from metal particles and glass powder.
816. thick-film capacitor - Capacitor consisting of two thick-film
layers of conductive film separated by a deposited thick-layer dielectric film.
817. thin film capacitor - Capacitor in which both the electrodes
and the dielectric are deposited in layers on a substrate.
818. transducer - Device that converts energy from one form to
another.
819. Transformer coupled Amplifier : It is a cascade amplifier using a
transformer as the coupling element.
820. transformer coupling - Also called inductive coupling.
Coupling of two circuits by means of mutual inductance provided by a
transformer.
821. transmission line - Conducting line used to transmit signal
energy between two points.
822. transmission - Sending of information.
823. Transmitter : it is a device which can send the
data to medium or channel.
824. Tree : It is a connected sub-graph of a
network which consists of all nodes of the original graph but no closed path.
825. triangular wave - A repeating wave that has equal positive
going and negative going ramps. The ramps have linear rates of change with
time.
826. Triode: A three-terminal electron device, such as a bipolar
junction transistor or a field-effect transistor.
827. troubleshooting - Systematic approach to locating the cause
of a fault in an electronic circuit or system.
828. tuned circuit - Circuit that can have its component values
adjusted so that it responds to one selected frequency and rejects all others.
829. tunnel diode - Heavily doped junction diode that has negative
resistance in the forward direction of its operating range.
830. Twigs : The branches of tree are called
twigs.
831. UJT : it is a three terminal device
which exhibits negative resistance region. That means in this device exhibits
the property “the voltage is inversely proportional to current”.
832. ultrasonic - Signals that are just above the frequency range
of human hearing of approximately 20 kHz.
833. Uni junction Transistor : it is a three terminal device
which exhibits negative resistance region. That means in this device exhibits
the property “the voltage is inversely proportional to current”.
834. Unilateral Elements : These are the elements, which are
not having voltage-current relation is same for current flowing in both
directions. Diodes are examples for these elements.
835. valence shell - The outermost electron shell for a given
atom. The number of electrons in this shell determines the conductivity of the
atom.
836. variable resistor - Resistor whose resistance can be changed
by turning a shaft. See also "potentiometer and rheostat."
837. Variable resistor: A resistor for which the resistance value can
be changed by the user, but must be independent of other outside influences.
838. vector diagram - Arrangement of vectors showing phase
relationships between two or more AC quantities of the same frequency.
839. Vestigial sideband modulator: In
this modulation we can transmit one sideband and vestige of other side band.
840. video - Relating to any picture or visual information.
841. voltage drop - Voltage or difference in potential developed
across a component due to current flow.
842. Voltage Regulator: A circuit which maintains the output voltage of
an ordinary power supply constant irrespective of changes in input voltage or
load variations.
843. Voltage standing wave ratio: Ratio of the maximum voltage
amplitude on a line to the minimum voltage amplitude.
844. Voltage: The difference in potential energy of the chargers is
called potential difference. In electrical terminology it is known as voltage.
Its units are volts.
845. Volts: It is the units for voltage.
846. Watt:The unit of power. It is equal to one joule per second.
847. wattmeter - Instrument used to measure electric power in
watts.
848. Waveform:it is the graphical representation of wave
849. Waveguide: A closed metal cylinder, filled with a dielectric, used
to transport electromagnetic energy over short or long distances.
850. Wavelength division multiplexing: it is the process of combining
and splitting signals on the basis of difference in their wavelengths.
851. weber - (Wb) Unit of magnetic flux
852. White noise: the signal contains equal power within a fixed
bandwidth at any center frequency.
853. WiMax - A way to transmit very high bandwidth connections
over a distance of up to 30 miles
854. Wireless communication: Transfer of information over a distance
without the use of electrical conductors or wires
855. Wireless: it is the medium for telecommunication for sending
signals by means of electromagnetic waves.
856. Zener Breakdown: In reverse biased PN junction, ionization by
electric field is known as Zener break down.
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