DIPOLE
Dipoles consist of two arms, each connected
to one side of the radio circuit feedline. Can be
constructed from stretched lengths of wire or
rigid metal tubing. “Rabbit ear” TV antennas
are a common example. Used for nearly every
radio band. Size ranges from huge to tiny.
Particular favorites of the amateur radio aka
ham community.
A
Horizontal, Vertical, and Diagonal — Mounted
horizontally, a dipole radiates broadside to
the length of the wires, with nulls (directions
in which it can’t receive) at either end.
Mounted vertically, a dipole radiates in an
omnidirectional 360° pattern (since the nulls
point up and down). When one end is mounted
higher than the other, it’s called a sloper and
the radiation pattern changes with the angle
of slope.
B
Inverted V and L — Dipoles are often
mounted with the highest point in the center
and the two arms angled down, usually at
a 120° or 90° angle. Inverted-vee dipoles
provide a more omnidirectional pattern than
a horizontal. Dipoles can also be mounted
with one arm horizontal and one vertical, in an
L-dipole configuration. This is usually due to
space constraints.
C
Folded — When the far ends of the dipole
are connected with a parallel wire, the result
looks like a flattened oval and is called a
folded dipole.
SKILL BUILDER Antenna Spotting
ANTENNA
SPOTTING
FIELD GUIDE
Antennas are all around us, but what does
each kind actually do? Here are a variety of
different types, and how they’re used. See
how many you can find near you!
makezine.com118
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M78_112-21_SB_Antennas_F1.indd 118M78_112-21_SB_Antennas_F1.indd 118 7/10/21 3:00 PM7/10/21 3:00 PM
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