How to choose a UHF antenna.

Choosing the right UHF (Ultra High Frequency) antenna is key for making sure your voice gets where it needs to be heard. Whether you’re setting up walkie-talkies, or in-car UHF, knowing a bit about antennas can make a big difference. Read on to have UHF antennas explained! One big thing to understand is antenna gain.

What’s Antenna Gain?

Antenna gain is kind of like a finite resource —if the signal is sent far in one direction, the other directions are limited. The signal can either be pushed out equally in all directions in a sphere shape, called unity gain.

All antenna gain is measured against an isotropic radiation pattern. Antenna gain is all about how much extra power an antenna gives out in a specific direction compared to this isotropic pattern, and you’ll often see it measured in dBd, dB or dBi. Unity gain is 0dBd, or 2.1dBi. Higher gains such as 6 dBd/8.1 dBi will push signal out in an oval shape, rather than equally in all directions.

What dBi Antenna Do I Need?

Theres plenty of antenna gains available, for handhelds, in-car UHFs and more. If you’re wondering, does the length of my aerial matter? The answer is sort-of! Generally higher gain antennas will be tall, and lower gain will be short. But one is not better than the other, they both work in different scenarios.

• City, Sand Dunes or Hills: If you’re in a city jam-packed with buildings and other obstacles, or other area where there is low line of sight, low-gain antennas are your go-to. They help your signal navigate through all the chaos.

• Country Areas: Out in the countryside with fewer obstacles and longer distances to cover, high-gain antennas are the way to go. They’ll push your signal further horizontally, to help your transmissions travel far and wide.

• On-the-Go: For those going all over the place, you can always get an interchangeable whip setup. This allows you to unscrew your low gain antenna once you get out of the city, and put on your high gain antenna.

In-car UHF radios are very customisable with what type of antenna you use and where you put it, whereas handhelds can be a little more limited. Most handhelds have replaceable antennas, just search for the model of your two-way or connector type to see whats available.

Comparing Antenna Types – What antenna should I use with my UHF?

Now that you’ve decided on the best gain for your situation, let’s talk about some different keywords you might come across when searching for UHF antennas:

1. Heavy Duty: Heavy-duty antennas are built tough to handle rough outdoor conditions. Get one on a spring base for some flexibility, and to minimise damage to the antenna from vibrations. These antennas are a great choice for bullbars or other areas where they may have to withstand some abuse.
2. Elevated Feed: Elevated feed antennas are exactly what the name suggests. The signal radiating part of the antenna is up higher, which helps them avoid interference from stuff on the ground, or your car. This gives you a clearer signal if you have an antenna mounted somewhere low. It is also Ground Independent (see below).
3. Ground Independent/Ground Dependent: Ground dependent antennas require mounting on a ground plane (a large flat metal plane, such as a car roof). If not mounted on a ground plane, signal is greatly impacted. Ground independent antennas can be mounted anywhere, bullbars, fenders or roof racks.
4. Radome: Radome antennas have a protective housing to shield the antenna elements. This is generally made of plastic, fibreglass, or another material that does not interfere with the signal.
5. Fibreglass: Good for 4WD vehicles and offroad use as they can withstand more vibration than a stainless steel antenna.
6. Whip: The antenna whip is the long part of the antenna! It can often be separated from the base to allow you to swap out your whip for one of a different gain. Additional antennas are often sold as ‘Replacement Whips’.

What’s the best UHF antenna?

Picking the best UHF aerial is all about understanding what you need it for. Choose a low gain antenna with a spring base if you’re 4WDing through hilly areas, or a high gain elevated feed antenna if you’re travelling the outback and need to mount the antenna on the bullbar.

Before choosing an antenna, figure out what terrain you’ll be using the antenna in, and where you’re mounting your antenna. This will tell you what gain you’ll need, and what other features you’ll need, such as a heavy-duty whip, spring base or ground independence. Check out some of our favourite options below to get started, or use the filters when browsing antennas to narrow down your search.

Keep these tips in mind, and you’ll be good to go! If you’re a visual learner, this video from GME is a great resource. Remember, you can always give Electric Bug a call if you have any questions!

Medium/High Gain UHF Antennas

Ground Independent Antennas

Flexible Antennas