Advanced Qualification · A-007 Feedlines and matching · A-007-007-004
Why is a ground-mounted vertical quarter-wave antenna in reasonably open surroundings better for long distance contacts than a half-wave dipole at a quarter wavelength above ground?
- AIt has an omnidirectional characteristic
- BIt uses vertical polarization
- CThe vertical radiation angle is lower
- DThe radiation resistance is lower
Correct answer: C — The vertical radiation angle is lower. From the official ISED question bank, verified word for word.
Why
A ground-mounted vertical quarter-wave antenna sends most of its signal at a low angle toward the horizon, which is ideal for bouncing off the ionosphere to reach distant stations. The full explanation — and one for every question — is in Pro.
Practise this section
Feedlines and matching is section A-007 of the Advanced exam: Feedlines and matching at the advanced level: transmission line theory, impedance transformation, stubs and matching networks.
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