Basic Qualification · B-006 Feedlines and antenna systems · B-006-009-001
How is a parasitic antenna element energized?
- A By direct connection to a driven element
- B By direct connection to the transmission line
- C By inductive coupling from a wave trap
- D By induction or radiation from a driven element
Correct answer: D — By induction or radiation from a driven element. From the official ISED question bank, verified word for word.
Why
A parasitic element has no wires attached to it; instead, it picks up energy from a nearby driven element through the invisible radio waves (radiation) or magnetic fields (induction) that the driven element creates. 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.