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Antennas for ham radio: a practical start

A simple wire can work stations around the world when conditions are right, and the RSGB says antennas don’t need to be big or expensive to perform well. The usual first HF antenna is a half-wave dipole. Before you put up antennas for ham radio at home, check two rules: most amateur aerials need planning permission, and above 10 W EIRP you must check EMF exposure.

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Updated October 2026 · Written from official sources, listed at the bottom of this page

Your first antenna: the half-wave dipole

  • Length: about 143 divided by the frequency in MHz, in metres. By our arithmetic that’s about 20 m for 7.1 MHz. Cut it a little long and trim it.
  • Feed it in the centre with 50 ohm coax such as RG213 or RG58. A balun is ideal, because the dipole is balanced and coax isn’t.
  • Keep the ends at least 3 m up if you can, and out of reach, since they carry high voltage.
  • A 40 m dipole also works on 15 m. Forcing it onto other bands with a tuner is inefficient.
  • With one mast, you can raise the centre and slope the ends down as an inverted-V.
RSGB: The half-wave dipole ↗

Antennas the Foundation syllabus names

The Foundation syllabus names five antennas you must recognise:

AntennaWhat the syllabus and RSGB say
Half-wave dipoleAbout half a wavelength long. Mounted vertically it’s omnidirectional; horizontal, it radiates most at right angles to the wire. The RSGB’s usual first HF antenna.
YagiA beam: a driven element, a slightly longer reflector and one or more slightly shorter directors. Higher gain, because it focuses radiation in one direction.
Quarter-wave ground planeA vertical that’s omnidirectional.
5/8-waveA vertical that’s omnidirectional.
End-fed wireA wire fed at one end. The RSGB has a beginner’s page on it.
RSGB: End-fed wire antennas ↗

Which coax and SWR meter for ham radio antennas?

Most radios have a 50 ohm unbalanced output, so use 50 ohm coax. Losses go up with frequency. RG58 can do on the lower HF bands over a short run, RG213 is a good general HF choice, and low-loss cables such as WestFlex, Ecoflex, Aircell and Aircom Plus suit 2 m and 70 cm better.

An SWR meter is essential for setting up an antenna, and in a car you’ll definitely need one. Check it covers your bands, since some are HF only. Tune a dipole by finding where the SWR is lowest: if that’s too low in frequency, shorten the wire. An antenna analyser shows more, but the RSGB doesn’t recommend one for complete beginners.

RSGB: Other equipment you need ↗

Masts, towers and planning permission

Most amateur aerials need planning permission from your local council. The exceptions the RSGB lists are usually TV-type antennas and ground-mounted ones up to 3 m (some councils allow more), anything up for less than 28 days a year, and truly mobile set-ups.

In England, from 25 April 2024, a home antenna has to stand unchanged for 10 years before it’s safe from enforcement, up from 4. Ones finished by 24 April 2024 stay under the 4-year rule, with a grace period to 25 April 2028. Wales, Scotland and Northern Ireland still use the 4-year rule. Changing or adding antennas can restart the clock.

RSGB members can use its planning advice booklet and planning panel.

RSGB: Planning matters ↗

Safety and EMF

  • Keep antennas, masts, ladders and tools well clear of power lines: at least twice the antenna’s height away. Treat every overhead line as live and uninsulated.
  • Don’t rely on fibreglass or wooden poles as insulators.
  • Work with a friend, and check for wiring and pipes before you drill.
  • If you run more than 10 W EIRP (6.1 W ERP), your licence requires you to check that people can’t be exposed above the EMF limits where they can be, and to keep a record. The RSGB’s EMF calculator works out the distances and suggests at least 2.4 m to stop people touching the antenna.
RSGB: Antenna safety ↗RSGB: EMF guidance and calculator ↗
Sources: RSGB and 7 more. Checked October 2026.

Rules and fees can change, so check the official site before your test.

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