- cable
Group of two or more insulated wires.
- CAD
- Abbreviation for "computer aided design"
- calibration
- To adjust the correct value of a reading by comparison to a
standard.
- capacitance
- The ability of a capacitor to store an electrical charge. The
basic unit of capacitance is the Farad.
- capacitive reactance
- The opposition to current flow provided by a capacitor.
Capacitive reactance is measured in ohms and varies inversly with
frequency.
- capacitor
- An electronic component having capacitive reactance.
- capacitor microphone
- Microphone whose operation depends on variations in
capacitance caused by varying air pressure on the movable plate of a
capacitor.
- carbon-film resistor
- Device made by depositing a thin carbon film on a ceramic
form.
- carbon microphone
- Microphone whose operation depends on pressure variation in
carbon granules causing a change in resistance.
- carbon resistor
- Resistor of fixed value made by mixing carbon granules with a
binder which is moulded and then baked.
- cascaded amplifier
- An amplifier with two or more stages arranged in a series
configuration.
- cascode amplifier
- A high frequency amplifier made up of a common-source
amplifier with a common-gate amplifier in its drain network.
- cathode
- The negative terminal electrode of a device. The "N" material
in a junction diode.
- cathode ray tube
- (CRT) Vacuum tube used to display data in a visual form.
Picture tube of a television or computer terminal.
- cell
- Single unit used to convert chemical energy into a DC
electrical voltage.
- center frequency
- Frequency to which an amplifier is tuned. The frequency half
way between the cut-off frequencies of a tuned circuit.
- center tap
- Midway connection between the two ends of a winding.
- center tapped rectifier
- Circuit that make use of a center tapped transformer and two
diodes to provide full wave rectification.
- center tapped transformer
- A transformer with a connection at the electrical center of a
winding.
- ceramic capacitor
- Capacitor in which the dialectric is ceramic.
- charge
- Quantity of electrical energy.
- charge current
- Current that flows to charge a capacitor or battery when
voltage is applied.
- chassis
- Metal box or frame into which components are mounted.
- chassis ground
- Connection to a chassis.
- chebyshev filter
- A type of active filter characterized by high roll-off rates
(40 dB per decade per pole) and midband gain that is not constant.
- choke
- Inductor used to oppose the flow of alternating current.
- circuit
- Interconnection of components to provide an electrical path
between two or more components.
- circuit breaker
- A protective device used to open a circuit when current
exceeds a maximum value. In effect a reusable fuse.
- clamper
- A diode circuit used to change the DC level of a waveform
without distorting the waveform.
- clapp oscillator
- A variation of the Colpitts oscillator. An added capacitor is
used to eliminate the effects of stray capacitance on the operation of
the basic Colpitts oscillator.
- class A amplifier
- A linear amplifier biased so the active device conducts
through 360 degrees of the input waveform.
- 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.
- class C amplifier
- An amplifier in which the active device conducts for less
than 180 degrees of the input waveform cycle.
- clipper
- A diode circuit used to eliminate part of a waveform
- clipping
- Distortion caused by overdriving an amplifier.
- clock
- A square waveform used for synchronizing and timing of
several circuits.
- closed circuit
- Circuit having a complete path for current flow.
- closed-loop gain
- Gain of an amplifier when a feedback path is present.
- coaxial cable
- Transmission line in which the signal carrying conductor is
covered by a dialectric and another conductor.
- coefficient of coupling
- The degree of coupling between two circuits.
- coercive force
- (H) Magnetizing force needed to reduce residual magnetism in
a material to zero.
- collector
- The semiconductor region in a bipolar junction transistor
through which a flow of charge carriers leaves the base region.
- collector characteristic curve
- A graph of collector voltage over collector current for a
given base current.
- color code
- Set of colors used to indicate value of a component.
- colpitts oscillator
- An oscillator with a pair of tapped capacitors in the
feedback network.
- common-anode display
- A multisegment light emitting diode (LED) with a single
positive voltage input connection. Separate cathode connections are
provided for each individual segment.
- common cathode display
- A multisegment light emitting diode (LED) with a single
negative voltage input connection. Separate anode connections are
provided for each individual segment.
- common base amplifier
- A BJT circuit in which the base connection is common to both
input and output.
- common collector amplifier
- A BJT circuit in which the collector connection is common to
both input and output.
- common drain amplifier
- A FET circuit in which the drain connection is common to both
input and output.
- common emitter amplifier
- A BJT circuit in which the emitter connection is common to
both input and output.
- common gate amplifier
- A FET circuit in which the gate connection is common to both
input and output.
- common source amplifier
- A FET circuit in which the source connection is common to
both input and output.
- 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.
- common-mode signals
- Signals that appear simultaneously at two inputs of an
operational amplifier (op-amp). Common mode signals are always equal in
amplitude and phase.
- comparitor
- An op-amp circuit that compares two inputs and provides a DC
output indicating the polarity relationship between the inputs.
- complementary symmetry amplifier
- A class B amplifier using matched complementry transistors.
Does not require a phase inverter for push-pull output.
- complementry transistors
- Two transistors, one NPN and one PNP having near identical
charastics. N-channel and P-channel FETs can also be complementry.
- complex numbers
- Numbers composed of a real number part and an imaginary
number part.
- compliance
- The maximum possible peak-to-peak output of an amplifier.
- constant current circuit
- Circuit used to maintain constant current to a load having
resistance that changes.
- contact
- Current carrying part of a switch, relay or connector.
- continuity
- Occurs when a complete path for current exists.
- conventional current flow
- Concept of current produced by the movement of positive
charges towards the negative terminal of a source.
- copper loss
- Power lost in transformers, generators, connecting wires and
other parts of a circuit due to current flow through the resistance of
copper conductors.
- core
- Magnetic material within a coil used to concentrate the
magnetic field.
- coulomb
- Unit of electric charge. A negative coulomb charge consists
of 6.24 × 1018 electrons.
- counter electromotive force
- (counter emf) Voltage induced into an inductor due to an
alternating or pulsating current. Counter emf is always in polarity
opposite to that of the applied voltage. Opposing a change of current.
- coupling
- To electronically connect two circuits so that signal will
pass from one to the other.
- covalent bond
- The way some atoms complete their valence shells by sharing
valence electrons with neighbouring atoms.
- crossover distortion
- Distortion caused by both devices in a class B amplifier
being cut-off at the same time.
- crowbar
- Circuit used to protect the output of a souce from a short
circuited load. Load current is limited to a value the source can
deliver without damage.
- CRT
- Abbreviation for cathode ray tube.
- crystal
- Natural or synthetic piezoelectric or semiconductor material
with atoms arranged with some degree of geometric regularity.
- crystal-controlled oscillator
- Oscillator that uses a quartz crystal in its feedback path to
maintain a stable output frequency.
- current
- Measured in amperes, it is the flow of electrons through a
conductor. Also know as electron flow.
- current amplifier
- Amplifier to increase signal current.
- current divider
- Parallel network designed to divide the total current of a
circuit
- current feedback
- Feedback configuration where a portion of the output current
is fed back to the amplifier input.
- current-limiting resistor
- Resistor in the path of current flow to control the amount of
current drawn by a device.
- current mirror
- Term used to describe the fact that DC current through the
base circuit of a class B amplifier is approximately equal to the DC
collector current.
- cutoff
- Condition when an active device is biased such that output
current is near zero or beyond zero.
- cutoff frequency
- Frequency at which the power gain of an amplifier falls below
50% of maximum.
- cycle
- When a repeating wave rises from zero to a positive maximum
then back to zero and on to a negative maximum and back to zero it is
said to have completed one cycle.
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