Basic Qualification · B-006 Feedlines and antenna systems · B-006-013-001
What is a quad antenna?
- A A centre-fed half-wavelength long wire
- B A quarter-wavelength vertical conductor fed at the bottom
- C Four straight, parallel elements in line with each other, each approximately half-wavelength long
- D Two or more parallel four-sided wire loops, each approximately one wavelength long
Correct answer: D — Two or more parallel four-sided wire loops, each approximately one wavelength long. From the official ISED question bank, verified word for word.
Why
A quad antenna uses two or more parallel wire loops shaped like squares, where each side is roughly a quarter of a wavelength, making the total loop length about one full wavelength. The full explanation — and one for every question — is in Pro.
Practise this section
Getting the signal out: antennas, feedlines, SWR, baluns, matching, and why antenna length depends on frequency.