Vertical Antenna

Overview

A vertical antenna is a quarter-wavelength radiator worked against a ground plane or a set of radial wires. Because it radiates at a low angle to the horizon, it is well suited to long-distance contacts — but that same low angle means it needs a good ground system to work properly.

The radiating element and its counterpoise form the other half of the antenna. Where a dipole has two visible wires, a vertical hides its second half in the ground, and that is the part most often done badly. Insufficient radials raise the take-off angle and turn a distance antenna into a local one.

Bands and modes

Band coverage

Modes

Safety note

Using it well

• Lay as many radials as you can before worrying about the radiator.
• Bond the antenna base to the station earth with a short, wide conductor.
• Trim the radiator against an analyser rather than trusting the published length.
• Check the base matching network after the first winter — water ingress is common.