BasicB-006-013-001
What is a quad antenna?
C
Answer
Antennas and feed lines
Type
A
A quarter-wavelength vertical conductor fed at the bottom
B
A centre-fed half-wavelength long wire
C
Two or more parallel four-sided wire loops, each approximately one wavelength long
D
Four straight, parallel elements in line with each other, each approximately a half-wavelength long
Answer Notes
A quad antenna is a highly directional wire antenna consisting of two or more parallel four-sided (usually square) wire loops. The distinguishing feature of a quad is that the total perimeter of each individual loop is approximately one full wavelength at the operating frequency.
In a standard quad beam, one loop acts as the driven element connecting to the feedline, while the other parallel loops act as parasitic elements (reflectors or directors). This arrangement focuses the radio waves to provide gain and directionality.
Options describing straight, parallel elements refer to a Yagi-Uda antenna, not a quad. A quad relies specifically on closed, full-wavelength geometric loops.
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