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Homebrew Antennas
Building your own antenna is one of the best-value parts of amateur radio. A few pounds of wire or tube, a little arithmetic and an afternoon can give you something that outperforms a ready-made compromise. This guide covers which design to choose, what to build it from and how to tune it, with free calculators for each design.
Antenna advisor ↓
Tell it your band, space and skills and get a design to build and how to install it.
Hentenna calculator →
Width, height, feed-bar position and a tube cut list for the compact 5 dBd-class loop.
Pattern simulator →
See predicted radiation patterns and whether each antenna works as horizontal or vertical, and how tilting changes it.
Dipole, loop and more →
Dipole, inverted-V, EFHW, loops, quad, ground plane, J-pole and coax length calculators.
Antenna advisor: what should I build?
Answer a few questions about your band, space and skills, and get a ranked list of designs to build, with sizes and installation advice for the top pick. It updates as you change the answers.
Why build your own antenna?
The antenna does more for your signal than almost any other part of the station. Moving from a poor antenna to a good one can be worth far more than a bigger amplifier, and it costs a fraction of the price. Homebrew antennas also teach you how radio really works: wavelength, resonance, impedance and polarisation stop being abstract once you have measured a loop you made yourself.
Most designs begin with one number, the wavelength, which is 299.8 divided by the frequency in MHz, giving metres. Practical antennas are trimmed a few percent short of the free-space figure because of end effect and the speed of the wave in the conductor, which is why every calculator on this site uses an editable shortening factor.
Choosing a design
| Design | Size at your frequency | Polarisation | Typical feed impedance | Good for | Difficulty |
|---|---|---|---|---|---|
| Half-wave dipole Pattern → | See calculator | Horizontal (or vertical if hung vertically) | 50–75 Ω | First antenna on any HF band; reliable and forgiving | Very easy |
| Inverted-V Pattern → | See calculator | Mostly horizontal | About 50 Ω | One mast or tree support instead of two | Easy |
| End-fed half-wave Pattern → | See calculator | Follows the wire | 2000–5000 Ω (needs transformer) | Portable and multiband operation | Easy, transformer needs care |
| Full-wave loop Pattern → | See calculator | Either, set by feed point | 100–120 Ω | Quiet reception and a single-band all-rounder | Moderate |
| Two-element quad Pattern → | See calculator | Either, set by feed point | 50–70 Ω | Directional gain from wire or tube | Moderate |
| Ground-plane vertical Pattern → | See calculator | Vertical | About 36–50 Ω | Omnidirectional VHF/UHF and low-angle HF | Easy |
| J-pole Pattern → | See calculator | Vertical | About 50 Ω at the tap | Cheap, rugged VHF/UHF base antenna | Easy |
| Hentenna Pattern → | See calculator | Horizontal upright; vertical on its side | 50–70 Ω reported | Compact loop with Yagi-like gain, popular on 6 m and 2 m | Moderate |
Sizes follow the frequency in the advisor above, and each design name opens its calculator at that frequency. Impedances are typical figures; real values depend on height, conductor thickness and surroundings.
Vertical, horizontal or both?
Polarisation is the orientation of the wave's electric field, and it follows the orientation of the radiating part of the antenna: a horizontal wire gives horizontal polarisation, a vertical whip gives vertical. It matters most on line-of-sight VHF and UHF paths, where a mismatched pair of antennas is often quoted as losing up to about 20 dB in the ideal case. Reflections from buildings and terrain usually soften that in real life, but a mismatch is still worth avoiding. On HF skywave paths the ionosphere scrambles polarisation, so height above ground and take-off angle matter far more than which way the wire points.
| Antenna | Polarisation | How to change it |
|---|---|---|
| Half-wave dipole | Horizontal as a flat-top; vertical if hung as a vertical wire | Orientation of the wire |
| Inverted-V | Mostly horizontal, with a vertical component from the sloping legs | Wider apex angle gives more horizontal |
| End-fed half-wave | Follows the wire: horizontal, mixed (sloper) or vertical | Orientation of the wire |
| Full-wave loop and quad | Set by the feed point: horizontal or vertical | Move the feed to a horizontal or a vertical side |
| Ground-plane vertical | Vertical | Fixed |
| J-pole | Vertical | Fixed |
| Hentenna | Horizontal when upright; vertical when turned 90° on its side | Rotate the loop in its own plane |
To see this for yourself, open the pattern simulator, which shows the predicted radiation pattern of each design and how tilting or re-feeding it moves the signal between horizontal and vertical.
Compromise installation
- Follow the mode you use most. On VHF/UHF, SSB, CW and weak-signal digital modes such as FT8 are conventionally horizontal, while FM voice, repeaters, packet and APRS are usually vertical. Check what local operators in your area use.
- Slant at 45°. Tilting a hentenna, loop or quad to 45°, or using a sloping wire, gives a mixed signal that is theoretically about 3 dB down against either polarisation. That is a modest, predictable loss compared with a full cross-polar mismatch.
- Use two antennas. A vertical ground plane or J-pole for FM and a horizontal dipole or hentenna for SSB, switched at the shack with a coax switch, is simple and cheap.
- Choose loop feed deliberately. A wire loop can be re-fed from the bottom side (horizontal) or a vertical side (vertical) later with little extra work, so you can test both.
- HF: keep it simple. A horizontal dipole or inverted-V, a quarter to half a wavelength up, is a good all-round compromise. A vertical only works well with a decent radial or ground system.
- Mind the surroundings. Keep any antenna clear of metal masts, guttering and wiring, ideally on a fibreglass or PVC mast section, because nearby metal shifts tuning and distorts the pattern. Indoors or in a loft, reflections make polarisation less predictable, so the compromise matters less.
Materials and tools
Conductors
Stranded copper-clad steel wire is strong and cheap for HF. Hard-drawn copper wire stretches less but is heavier. For VHF and UHF, copper pipe, aluminium tube or brass rod keep their shape.
Insulators and spreaders
Fibreglass poles, PVC conduit, dowel or plastic cable ties make good spreaders. Avoid metal fittings near the high-voltage ends of an antenna.
Feedline and choke
Use good coax, keep joints weatherproof, and add a current balun or a few turns of coax as a choke at the feed point of balanced antennas.
Test gear
A NanoVNA or antenna analyser shows resonance and SWR across a whole band without transmitting, and is the single most useful tool for tuning homebrew work.
Tuning your antenna
- Cut conductors a little longer than the calculator value, since you can shorten wire but never lengthen it.
- Raise the antenna to roughly its final height and keep it away from metal, guttering and wiring.
- Sweep it with an analyser and find the frequency of minimum SWR.
- If resonance is too low, trim equal amounts from each end. If it is too high, lengthen. As a rule of thumb, small changes move resonance more on a short antenna than a long one.
- Add the choke or balun, then re-check the sweep, because changing the feed arrangement can move resonance slightly.
Fun designs worth trying
The hentenna is an unusual Japanese rectangular loop that combines a loop and a matching section in a single frame, and gives surprisingly good gain from a small structure. The J-pole is a classic first project for 2 m and 70 cm. A full-wave loop is a favourite for quiet reception, and a simple wire quad gives directional gain without a heavy boom. Each has a calculator on this site: start with the dipole, loop, quad and J-pole calculators.
Homebrew antenna FAQ
What is the easiest homebrew antenna to build?
A half-wave wire dipole fed with coax and a 1:1 balun: two lengths of wire, a centre insulator and two end insulators.
What do I need to tune a homemade antenna?
An antenna analyser or NanoVNA is ideal. A transceiver with a built-in SWR display or a separate SWR meter will also do the job, though it needs transmitting.
Do homebrew antennas need a balun or choke?
Balanced antennas such as dipoles and loops usually benefit from a 1:1 current balun or a coax choke, which reduces common-mode current on the feedline.
Are antennas I build myself legal?
In the UK, licensed amateurs may build and use their own antennas on their licensed bands within the licence conditions. Check the current terms for power, bandwidth and exposure.
Should it be vertical or horizontal?
Match the stations you want to work: horizontal for SSB, CW and weak-signal digital modes on VHF/UHF, vertical for FM and repeaters. A 45° slant costs about 3 dB against either, or use one of each. See the polarisation guide above.
How accurate are the calculators?
They give a starting length based on standard formulas. Real resonance depends on height, nearby objects and conductor, so always verify with an analyser and trim.