Technical Articles

Dipole vs Vertical: Which Antenna is Better?

The dipole versus vertical question doesn’t really have a single “right” answer, and amateurs will offer different responses based on their individual preferences. It’s almost like the Ford versus Chevy argument. Both get you from point A to point B, but there’s always the claim that one is superior to the other.

Vertical

The basic quarter-wave vertical antenna is essentially half of a dipole with the other half of the antenna composed of radials, either at or above ground. One of the primary advantages of HF vertical antennas is that they are omnidirectional, meaning they transmit and receive in all directions.

With a good set of radials, these antennas produce a low angle of radiation. This reduces the number of hops that HF radio signals must make to reach their destination, and makes them a good choice for DX—especially on the low bands. By comparison, a horizontally-polarized antenna needs to be a half wavelength above ground to have similar low-angle performance.

Verticals can be mounted on roofs, towers, poles, or at ground level. The ones that are ground mounted are less noticeable to neighbors and easier to maintain. Those that are elevated above ground require fewer radials—two minimum per band, but four is better. If you don’t have the space to install standard length radials, there are verticals that utilize a group of short radials with broadband matching unit. They’re typically mounted eight feet or more above ground level.

You’ve probably noticed that most Ham mobile radios and HTs use vertical antennas. Part of the reason is that they conserve space and mount easily on vehicles. VHF/UHF propagation is line of sight, and traditionally vertical antennas have been the choice for portable or mobile—whether it’s simplex or via a repeater.

On the downside, verticals have a reputation for picking up more noise than a horizontal antenna in AM/CW/SSB modes. They tend to be more sensitive to vertically-polarized noise generated by lightning or overhead power lines. They also tend to be more expensive to buy and have the additional cost of adding radials.

Horizontal Dipole

The horizontal dipole is the simplest and most widely used type of antenna. They’re easy to put up for temporary or Field Day use, and they’re also widely used by radio amateurs at home because they’re inexpensive and easy to build. Another advantage of dipole antennas is they are very efficient when used at their resonant frequency.

Dipole antennas are mostly omnidirectional when sending and receiving signals. Dipoles can be hidden in trees, attics, and along roof lines to keep your HOA happy.

Though horizontal dipoles are relatively easy to make, they often take some effort to install in trees or on poles and towers. Height also matters—the higher the dipole, the better. Ideally, a dipole should be at a half wavelength above ground for best performance and making DX contacts. At 40 meters, that would be 33 feet. But many Hams report they can still get good performance at lower than half wavelength heights.

You can erect dipole antennas in a variety of configurations to meet your needs: flat-top, inverted-V, sloping dipole, or folded dipole. There are even variations of the dipole that can cover multiple bands, like trap dipoles, parallel dipoles and off-center-fed (OCF) dipoles.

One of the disadvantages of a horizontal dipole is length, especially on the low frequencies. Since the dipole is typically a half-wave antenna, it can be impractical on small lots. For the 80 meters band, the length would be 130 feet; 160 meters would extend 260 feet.

The Answer?

If cost is your primary consideration, the horizontal dipole is a great choice. All you need is wire, insulators, and some support rope to build this simple antenna. Just be sure you have two supports, such as trees or poles to hang the dipole. Remember, higher is better. If you only have one support, you can droop the ends into an inverted-V configuration, which can also save space.  Be sure the ends of your inverted-V are at least eight feet above ground so they aren’t a danger to humans and pets.

DX chasers should consider the vertical. They don’t take up much space, many are less than 30 feet high, and most don’t require supports other than a few guy lines. Vertical antennas naturally have a low angle of radiation, meaning you’ll have a good chance of making worldwide contacts.  The downside is that they can cost several hundreds of dollars, require more time to assemble, and need radials.

If you’re having trouble deciding, why not use both varieties? I never considered my antenna farm complete until I had both vertical and horizontal antenna options on all HF bands. And I managed to squeeze them all into a 0.3 acre suburban lot, enjoying the advantages of both.

Vertically-polarized antennas and horizontally-polarized antennas also complement each other very well. Where one works poorly, the other may perform well. You might be surprised at what the vertical can pull in that the dipole can’t and vice versa. With changing propagation, it’s a winning combination for maximizing contacts.

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