waveform will be repeated
as the loop continues to
rotate
in
the
magnetic
field, and the number of
cycles that occur in a
given period of time will
depend on the speed at
which the loop is rotated.
The number of cycles that
occur in a given period of
time
is
called
the
The unit of
is
the
Hertz
(Hz), which is one cycle
per second.
Two prefixes
are used in referring to
the
higher
frequencies.
For example:
1 kilohertz (kHz)
= 1,000 Hz
1 megahertz (MHz)
= 1,000,000 Hz
13.
AC CIRCUIT COMPONENTS
in
a
circuit
restricts the flow of both ac and dc.
However, in ac circuits there is an
opposition to the flow of current in
addition to the resistance of the
circuit.
This opposition to ac is
offered by inductors and capacitors in
the circuit.
a. Inductors.
Inductors appear
in many types and sizes, depending on
the application.
Regardless of their
size and shape, they all consist of
turns of wire, or copper tubing. Some
have iron cores, and others are hollow
(air
cores).
Their
construction
depends on the task to be performed.
(1) Most of the coils used in
radio
work
are
fixed
inductors, which have a
constant
value
of
inductance in a circuit.
Coils that are hollow (air
core) are usually designed
to
handle
alternating
at
radio
frequencies,
Figure 18. Some types of inductors
used in radio circuits.
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