18WuD2x

100 Carey-Foster bridge • carrier line
Carey-Foster bridge A special version of the slidewire
bridge that is useful for measuring an unknown
resistance, whose value is close to that of
a standard resistance.
R X
R1
Slide
wire
S1
S2
Carey-Foster bridge
Carey-Foster mutual inductance bridge An ac
bridge that permits the measurement of mutual
inductance in terms of a standard capacitor.
R1
C
L1
R3
M
Det
Gen
R4
R 2 = 0
R2
R3
M = R 1 R 4 C
R 3 = R 4 ( L 1 −1)
M
Carey-Foster mutual inductance bridge
carnauba wax A wax obtained from the Brazilian
wax palm. Used as an electrical insulator, and as
the dielectric in some electrets.
Carnot theorem In thermodynamics, the proposition
that in a reversible cycle, all available energy
is converted into mechanical work. Also called
Carnot’s principle.
carrier 1. See CARRIER WAVE. 2. See CHARGE
CARRIER.
carrier amplifier See DIELECTRIC AMPLIFIER.
carrier beating 1. The mixing of two radiofrequency
carriers that are separated by a small
amount of frequency, resulting in an audible tone
in a receiver. 2. A heterodyne in a facsimile or
television signal, resulting in a pattern of cross
hatches in the received image.
carrier choke A radio-frequency (RF) choke, inserted
in a line to block a carrier component.
carrier chrominance signal For conveying color
television information, sidebands of a modulated
chrominance subcarrier.
carrier color signal For conveying color information
in color television transmission, the sidebands
of a modulated chrominance subcarrier
(plus the unsuppressed chrominance subcarrier)
added to the monochrome signal.
carrier concentration In a semiconductor material,
the number of charge carriers per unit volume.
carrier control 1. The modification, adjustment,
or switching of a carrier wave. 2. Adjustment of a
circuit or device by means of a carrier wave.
carrier current The current component of a carrier
wave, or the amplitude of that current. Compare
CARRIER POWER and CARRIER VOLTAGE.
carrier-current communication See WIRED
WIRELESS.
carrier-current control 1. Control of the current
component in a carrier wave. 2. Remote control
by means of wired wireless.
carrier-current receiver See WIRED-RADIO RE-
CEIVER.
carrier-current relay A radio-frequency (RF) relay
circuit, operated over a wire line by means of a
transmitter.
carrier-current transmitter See WIRED-RADIO
TRANSMITTER.
carrier deviation See CARRIER SWING.
carrier dispersion In a semiconductor, the spreading
out of electrons and holes that leave the emitter
simultaneously, but arrive at the collector at
various times after following different paths.
carrier frequency The center frequency of a CAR-
RIER WAVE.
carrier-frequency pulse A pulse that contains
radio-frequency oscillation.
carrier-frequency range The band of carrier frequencies
over which a transmitter or signal generator
can operate.
carrier injection The apparent emission (injection)
of electrons or holes into a semiconductor when a
voltage is applied to the junction.
carrier leak 1. A point at which carrier-wave energy
escapes a circuit or enclosure. 2. The residual
carrier voltage present in the output of a
carrier-suppressing circuit.
carrier level The amplitude of an unmodulated
carrier wave.
carrier lifetime In a semiconductor, the interval
before an injected current carrier (see CARRIER
INJECTION) recombines with an opposite carrier
and ceases to be mobile.
carrier line
In carrier-current systems (see WIRED
WIRELESS), the line or cable conducting the
carrier-wave energy.