Basic Qualification · B-006 Feedlines and antenna systems · B-006-010-009
How can a vertical antenna, 2 metres in length, be made to resonate in the 80-metre band for mobile use?
- AUse a solid radiating element instead of tubing
- BInstall a capacitor in series with the antenna
- CConnect the transmission line shield to the vehicle's chassis
- DInstall an inductor in series with the antenna
Correct answer: D — Install an inductor in series with the antenna. From the official ISED question bank, verified word for word.
Why
A 2-metre antenna is far too short to naturally resonate on the 80-metre band because it lacks the electrical length needed to store energy efficiently. The full explanation — and one for every question — is in Pro.
Practise this section
Feedlines and antenna systems is section B-006 of the Basic exam: Getting the signal out: antennas, feedlines, SWR, baluns, matching, and why antenna length depends on frequency.
Drill B-006 — free, no account