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If I only have the budget for one HF antenna, should I chose a vertical or a horizontal antenna?

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    $\begingroup$ If budget is your primary concern, all you need is some coax and some wire and you can throw up a dipole in minutes. On HF, Horizontal is preferable anyway. On the lower frequencies (75) your primary work wiill be with ground waves. On higher (40/20) it can also be by skywave which tends to rotate unpredictably as it interacts with the ionosphere. Since most people tend to use Horizontal means that your signal-to-noise ratio will be worse if you are using a vertical. i.e. you will hear more QRN (Natural noise). Wire antennas are always least expensive, and there are a ton of varieties. $\endgroup$ – SDsolar Jul 16 '17 at 7:50
  • $\begingroup$ I see this was posted 3 years, 8 months ago Funny it would pop up now. But it is a great question all the time. So hello from the Future, Timtech. (July 2017) $\endgroup$ – SDsolar Jul 16 '17 at 7:56
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    $\begingroup$ Thanks @SDsolar, thankfully my diagonal antenna allowed me to time travel, so I'll be heading back to 2013 and tilting it until it's horizontal. $\endgroup$ – Timtech Jul 17 '17 at 0:45
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Summary

If you can have only one antenna and can chose between a vertical HF antenna or a relatively high horizontal HF antenna, go for the horizontal antenna.

Modelling results

In January 2008, L. B. Cebik, W4RNL (SK) published what was going to be the last entry of his seminal 10-10 News series. It turned out to be an interesting gain comparison of single element 28.4MHz antennas modelled over various ground types of which a summary is presented here (Table 1). His findings seem to fit well with what John Devoldere, ON4UN modelled and published for equivalent antennas on the lower HF bands.

Gain & elevation angle of single element 28.4MHz antennas over various ground types

Horizontal HF antennas: near-by ground gain

At a height of about λ/2, the nearby ground reflection of a horizontal HF antenna will start to be constructive at interesting take-off angles for long- distance ionospheric contacts. This will provide a net gain over the antenna in free-space.

Vertical HF antennas: near-by ground loss

This is not the case with vertical HF antennas. Nearby ground only contributes loss. This even more so when the ground forms part of the return path of the radiating structure. Even when far-away ground reflections may cause the directivity of a vertical HF antenna at low take-off angles to be much higher than that of a horizontal HF antenna, its net gain will still be lower at those angles. This makes the horizontal HF antenna a clear winner, at least for what transmission is concerned. Note that gain and directivity are not synonyms; gain takes into account losses, directivity does not.

Vertical HF antennas still remain useful

Vertical HF antennas do have their merit though. At the lower end of the HF spectrum, the λ/2 height requirement for horizontal antennas can become cumbersome (even though a horizontal phased array may weaken this requirement by allowing somewhat lower heights). A vertical HF antenna can get away with a height of only λ/4. Furthermore, the directivity of a vertical HF antenna can be effectively employed at the reception end to cancel out high-angle interference by near-by stations. This is why some stations use receive-only phased-arrays of verticals on the low bands.

Polarisation at HF

Polarisation is not really an issue at HF (apart from lightning and man-made noise considerations). This is so because the ionosphere is mainly an anisotropic medium, i.e. it messes up polarisation.

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    $\begingroup$ This is a gross oversimplification. There are advantages to each -- but there's certainly no "clear winner". $\endgroup$ – Phil Frost - W8II Nov 11 '13 at 13:50
  • $\begingroup$ Here is what the late L. B. Cebik had to say about this: "...there are some good reasons for using a vertically polarized antenna on 10. Although the gain of such antennas may not usually compete with a well-installed horizontal antenna of the same size..." Read more here. $\endgroup$ – on4aa Nov 12 '13 at 0:48
  • $\begingroup$ @on4aa I don't see anything in that article to substantiate that claim. $\endgroup$ – Phil Frost - W8II Nov 26 '13 at 17:24
  • $\begingroup$ Bob Raynor, N4JTE, backyard testing: phased horizontal wires outperformed phased verticals on 80 & 40m in almost 100% of the single-blinded tests. $\endgroup$ – on4aa Nov 26 '13 at 21:38
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    $\begingroup$ @on4aa that's a cherry-picked result which uses phased arrays. It's likely that someone with only one antenna does not have an extensive array, and quite possibly whatever made one antenna better in that very specific test does not apply in the general case of a simple vertical/horizontal choice. $\endgroup$ – Phil Frost - W8II Feb 24 '14 at 20:05
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It doesn't really matter.

You're asking about a topic called polarization, which is really important in VHF and UHF. It's the reason why rotating your HT can improve or harm your reception, and it's also the reason why some 3D glasses and sunglasses work. But because of the way HF propagation works, it doesn't really matter. Any ionospheric propagation gets the polarization randomized anyway. Very short range (ground wave) HF works best with a vertical antenna, but it's very rare that you care more about short-range than long-range.

In terms of limited space and cost, it's probably easier to set up a horizontal antenna (or an inverted V like a G5RV or OCF) than a vertical simply because it's easier to string a wire through some trees than it is to secure a flagpole or tower against gravity and wind loads.

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    $\begingroup$ Oh okay, I'm not really familiar with polarization. $\endgroup$ – Timtech Oct 22 '13 at 23:34
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    $\begingroup$ It's easier to get NVIS HF with a horizontal than vertical antenna, and NVIS on HF is a lot more useful than ground wave on HF. $\endgroup$ – a CVn Oct 23 '13 at 10:57
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    $\begingroup$ @MichaelKjörling that's a pretty broad statement. Ground wave on 80m can go pretty far. $\endgroup$ – Phil Frost - W8II Feb 24 '14 at 20:15
  • $\begingroup$ @PhilFrost-W8II It sure can! Even during the day. I spend a lot of time in QSOs -even during the day- with hams from my QTH in SW Missouri. You should join us! :-) Contact me for the frequencies, we'd love to have you! $\endgroup$ – Mike Waters Jul 16 '17 at 2:30
  • $\begingroup$ That is very true, @Phil. Especially at night. I grew up in Alaska talking with people all over the state using ham radio as their primary source of communications. Most of what I did over the years was Morse - I have log books full of contacts on 80 Meters. All on an inverted-V antenna strung from a 50 foot wooden tower. Alaska is a very large place, physically. About a third of the size of the whole US if you lay it over it. 80 Meter CW was pretty reliable. Sniper Net used SSB at 3905 had 20-30 regulars. $\endgroup$ – SDsolar Jul 17 '17 at 11:08
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There are useful tidbits in all the answers so far. Here are a couple more. Not every ham has the good fortune to have conveniently spaced tall trees to hang horizontal antennas from. On 80 meters to function well, a dipole antenna would be about 130 feet long (a half wave). Distance above ground for optimal performance would be the same distance. Probably not practical for most hams. The situation improves the higher in frequency you go--i.e 40 meters where the half wave length is about 66 feet with the corresponding reduction in optimal height. I guess what I'm saying is that, on 80 put up a dipole and get it as high as you can. It will still work at lower heights--just not as well. A vertical on 80 is also probably also impractical (unless you use "tricks" which will limit it's performance) since the vertical radiator would need to be a quarter wavelength long (66 feet) and many, many ground radials which would also be about that long. Commercially produced multi-band verticals make rather fantastic claims as to their performance. They tend to be poor performers when compared to a full sized horizontal antenna. They're also outrageously expensive. You can homebrew a dipole for far less than $50.00.

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    $\begingroup$ Thanks for your input, and welcome to ham.stackexchange.com! Please consider taking the tour to get the most from this site. $\endgroup$ – Mike Waters Jul 16 '17 at 2:06
  • $\begingroup$ Thanks for taking the time to answer my question! I've since decided that the horizontal HF is better overall but haven't yet considered homebrewing my equipment. $\endgroup$ – Timtech Jul 17 '17 at 14:47
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It matters only for local RF interference purposes. Once the signal hits the ionosphere, the polarization is randomized, thus it really doesn't make a difference.

Polarization of RF Interference tends to be vertically polarized, but that's such a small effect that it really probably doesn't matter which way you do the antenna.

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Very good answers posted about polarization. I must point out an important caveat about polarization - while not so important for distant skip contacts ... it IS a vital consideration for LOCAL contacts. Cost and convenience is a prime factor for the popularity of rooftop vertical HF antennae. If your local friends are using verticals - you need to also be on a vertical (polarization) otherwise they may not hear you clearly or at all. As noted in another answer, vertical does draw more interference in a typical cityscape, but it varies depending on your location and proximity to interference sources.

If local contacts are important, and if other locals are using verticals, then you should consider a vertical. If DX is more important, then other horizontal options present themselves (which may even work well for local contacts).

A different factor to consider is the construction of the particular vertical you intend to use. Some are simply a 50 ohm "dummy load" with a wavelength/fraction wire sticking out it. Some have grounding radials. Some have coils. Just classifying it a vertical antenna is not entirely accurate.

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  • $\begingroup$ What is "local" on HF? That seems like it would depend on power, antenna height, and a few other factors... $\endgroup$ – Adam Davis Jan 24 '14 at 21:04
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If I could have only one antenaa, any antenna, it be a 150' Big Bertha with stacked tribanders :)

Before a good answer can be made, we need some more information:

1) What bands are you interested in working? 2) Can you get a horizontal antenna at least λ/4 high and preferably λ/2 high? 3) Do you have an antenna tuner?

If I were flat broke and had high trees, I would make a fan dipole with one leg on 80m/75m, one leg 40m (gives you 15m for free as it's the 3rd harmonic) and one leg 10m. Depending on the situation, you could probably pull 20m out of either 40m leg or 10m with a close enough match to not need a tuner. Having one would tighten the match, but probably wouldn't make a noticable difference. Not counting the optional tuner, you would be hard pressed to spend $50 on this solution. You'd have resonant antennas on the primary bands and could work the world no problem.

If soldering 6 wires is a problem, and you had a tuner, a G5RV or clone would be an option. It's an all band solution, but is a compromise on all bands and a tuner is required for a good match. You can work a lot of countries with one, but it will set you back $75-$100 plus a tuner.

If I had no trees, or low trees or no good way to hang a dipole, I would go with a multiband vertical like the GAP Challenger DX. It uses stub matching and gives a no tuner between than 1.5:1 on all the HF bands plus 6m and 2m. It's a bit of a compromise on 80m and is worthless on 160m though. It uses 3 couterpoise wires instead of a large radial field and you can work the work 40m and up no problem (I have one). But it costs $350. There are cheaper ones, but they are more and more of a compromise especially the ones that use coils to make up for their physical size.

I have both a vertical and dipoles and I find the noise difference to be negligible, but that's certainly something that is going to vary by location. In a city or dense suburban area, RF trash from the neighbor's plasma TV might rule out a vertical (as a previous poster noted, most man-made RFI is vertically polarized).

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Well, speaking from a budget point of view, you can cover 80-6 for $100 with a multiband OCF dipole, but any HF vertical is going to require a lot more budget than that - probably at least 5 times that much, and more if you need to bury radials.

Most everything posted here is not relevant in light of the enormous cost difference between a well-performing dipole and a well-performing vertical for HF.

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    $\begingroup$ Hustler 4BTV and a spool of wire for radials can be had for \$200. If you want more bands you can put a tuner on it, just like you'd be doing with a dipole covering 80m to 6m. You can put a tuner on a much cheaper monoband vertical, for that matter. Or haul a \$2 piece of wire vertically into a tree. Not sure "five times as much" is a fair comparison. $\endgroup$ – Phil Frost - W8II Aug 5 '17 at 19:28
  • $\begingroup$ Most of the expense from doing a vertical antenna properly comes from renting the equipment to properly install the radials. I don't know too many people who want to bury a dozen 20m long radials with a shovel. $\endgroup$ – user2104506 Aug 6 '17 at 20:03
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    $\begingroup$ Why not hold the radials down with staples until the grass thatch grows over them? Or use a lawn edger? $\endgroup$ – Phil Frost - W8II Aug 15 '17 at 17:41
  • $\begingroup$ @user2104506 Phil is correct. That's what I do at the end of my Beverage RX antennas, and I know many hams who have done that with TX antennas. In a few weeks, the radials disappear into the lawn and are difficult to pull up. My last 2 verticals used just 2 elevated radials. 4 or 6 high enough to walk under is plenty!. Scroll down about half way to the "Relevant links". Also, with only 12 buried radials at the base of a λ/4 vertical, you'll lose over half of your power in earth losses. $\endgroup$ – Mike Waters Aug 15 '17 at 22:34
  • $\begingroup$ Above ground radials "high enough to walk under" are not only a maintenance nightmare but a safety and liability issue. And, you cannot know how many radials are required until doing a thorough soil study. The point of my post was not to say "you need 12 ground radials for any antenna," obviously. $\endgroup$ – user2104506 Aug 16 '17 at 18:52
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Horizontal.

However, one of the exceptions is 160 meters. If you are mostly interested on making longer distance QSOs (especially DX) contacts on 160, vertical polarization is best on that band. Period.

Check out this page. In a nutshell: What is effective on 160m are vertically-polarized antennas for transmitting, using separate antennas for receiving.

Per W8JI on qrz.com:

"Nearly all especially successful stations on 160 use a vertically polarized antenna of some type for transmitting. That's just a fact."

"The fact is....... an Inverted L with 20 or more radials at least 50 feet and hopefully 100 feet long will absolutely smoke any normal height loop antenna or dipole antenna at nearly any distance on 160 meters. The possible exception is between 20 and 200 miles."

"I have a full size 160 dipole at 300 feet, and it is never really much better than a 1/4 wave vertical at any distance in any direction. As a matter of fact, the dipole is 10-20 dB weaker than the vertical off the dipole ends. The dipole only beats the vertical broadside to the dipole, and then only rarely!! And this is with the dipole 300 feet above ground."

"As a matter of fact a low full wave loop has no gain, any horizontal wire has increased earth induced loss as it is made longer when close to earth."

http://forums.qrz.com/showthread.php?t=260716&highlight=beverage

Chart from ON4UN's Low Band Dxing,published by the ARRL

Having said that about 160 meters...

On 80 through 10, both vertical and horizontal antennas can be good choices. You should pick whichever is convenient to erect and/or will accomplish your objective.

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  • $\begingroup$ Technically, 160m is MF. But many folks consider HF as being 160-10. $\endgroup$ – Mike Waters Jul 16 '17 at 17:49

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