Basic Qualification · B-006 Feedlines and antenna systems · B-006-005-005
What is the main adverse effect due to operating with high SWR?
- A Increased transmission line radiation
- B Increased common-mode current
- C Increased transmission line loss
- D Increased receive noise level
Correct answer: C — Increased transmission line loss. From the official ISED question bank, verified word for word.
Why
When the standing wave ratio, or SWR, is high, much of the radio energy bounces back and forth along the feedline instead of reaching the antenna. 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.