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Best yagi/beam for 20m?

I’m looking to work DX as well as chase SOTA on 20m. I’m seriously considering putting up a beam (or some kind of directional high gain antenna).

This will be my first HF beam & after several hours sifting through all of the options from various suppliers I’m feeling a little bewildered!

I’m primarily looking to work DX into US, Japan, Australia, Africa, UAE etc and give myself a bit more of a fighting chance chasing SOTA on 20m.

What beams do other SOTA chasers use on 20m?

Here are my criteria/restrictions:-

  1. Budget is limited to £1000 absolute maximum, preferably less than £500 but would consider stretching the budget if there was a decent antenna worth the extra cash

  2. Space is a bit tight. I reckon that I can get away with a turning radius up to about 5m

  3. I have a reasonably substantial 12 meter tall mast which is concreted in to the ground (2mx2m concrete base, which is 1m deep). It should take a fair bit of weight, but I don’t want to push my luck! Let’s set a very conservative weight limit of around 15-20kg (although I suspect that the mast would handle 30kg plus).

From my research so far, I’ve got the following possibilities on the short list…

Mono-banders:-

  • ZX20-3 which is apparently designed by ON4UN, who wrote the book on DXing (very literally), so I would hope that it’s a good antenna!!!
    Turning radius is 5.6 (slightly bigger than my limit of 5m) but might be able to make it work if I move/remove the VHF/UHF colinear.

  • 20m Moxon from InnovAntennas.
    Has good front-to-back rejection, is smaller than most of the others, but has a slightly lower forward gain. That said, I’ve heard several good comments from people who have used them.It’s also the cheapest of the lot @ £300 (not sure if the cheap price should be causing alarm bells to ring)?!?!?!

Tri-banders (the extra bands would probably be useful, but I’m only really interested in 20M):-

  • G3TXQ Hexbean (made by several manufacturers)
    Heard a lot of people raving about these. Apparently they are very popular, especially for people with limited space. Much less forward gain than the other antennas though, although still fairly good front-to-back.

  • Cushcraft A3S
    On paper, it seems to be on a par with the two mono-banders listed above, giving me 21MHz & 28MHz to play with aswell as 20m. It is however more expensive @ £700

  • OptiBeam OB6-3M
    On paper this seems to have the best specs, but is also the most expensive @ £839. I guess you get what you pay for but I’m not sure if I can justify the additional cost over the other options.
    There seem to be several videos on YouTube made by people who own these, but no reviews as such.

Your thoughts?

I’m particularly interested in hearing from anyone who has hands on experience with any of the beams listed above.

My first thought is that your mast is going to need guying; I say that as a general rule as most masts I see in use are 1.25 - 2 inches diameter. That is a lot of moment on a mast that size, but again - you know your mast and I do not. My suggestion - that is something to give critical review analysis.

Now, as to the antenna: The Moxon is a sound antenna, though a two element Yagi may give a dB or two of gain. It will also be heavier and a larger turning radius.

That’s about all I can offer and hope it gives at least some help.

Howard KE6MAK

I had an A4S which really worked well. I think a tri-band yagi is the way to go. If you buy used, make sure to inspect the traps prior to puttng into the air.

Malen
VE6VID

Hi James,

The issue for your mast and its concrete base is not likely to be the weight/mass of the beam (and rotator I presume), but the wind loading based on the surface area of the beam (and rotator), and the rated wind peaks for your region. You may well find that a 1m depth of concrete is marginal for even the 3 element cushcraft. But the numbers need to be crunched to determine what wind loading your tower+antenna will create and whether your concrete base is sufficiently deep in the ground for it. I am currently preparing to mount a lattice steel tower (of the Versatower style) and the concrete base and supporting tube will be 2.2m in the ground, from memory, giving it much more leverage.

73 Andrew VK1DA/VK2UH

1 Like

I wouldn’t install any beam antenna for 20m plus rotator on a 10-12m high mast without guying. Once the antenna and rotator get on top of the mast, the mast will suffer huge efforts at its base under the lightest winds. Under strong winds it will bend and fall down very soon.
I’d recommend 2 sets of 3 or 4 guying lines at 4m and at 8m from the base of the mast. Dyneema cord is perfect for that.
I’ve had a 3 elements tribander and a 5 elements tribander, which is what I currently have. The 5 el. is made by Hy-Gain (TH5-DX) and it’s far too big for you 5m turning radius limit. The 3 elements one worked very well and it was smaller. I bought it second hand and I don’t remember the manufacturer name, but it was similar to the Hy-Gain TH3 Junior.
I’d go for a similar small 3 elements tribander. You are now mainly interested on 20m, but having 10 and 15 as well in your beam will give you a lot of satisfaction by little more money and nearly not bigger size.
Good luck with your project.
73,

Guru

Thanks for the comments folks.

As most people have said, the issue is going to be the wind loading rather than the weight. The mast is 90mm steel box section which is around 5-6mm thick (bottom section up to around 5.5 meters), so should be reasonably sturdy. The mast is telescopic, so can be (and usually is) lowered. I always leave it lowered when not in use, and more often than not, I also keep it in the lowered position when in use.

When the manufacturer installed it, I was advised by the manufacturer that if using it un-guyed, it will support a small/medium HF beam without any issues at it’s reduced height (6 meters) but be cautious about windspeeds if extending it to it’s full height (12 meters).

It’s survived about 5 years with a fairly large vertical, and several quite big VHF beams mounted on it all year round through some fairly bad storms, so I think that it will take a bit of abuse, though I still don’t want to push my luck!.

On the basis of some of the comments above, I thinking that the safe (& more sensible option) is to go for a smaller antenna and accept the reduction in gain.

In my eyes, that narrows it down to two possibilities. I’m thinking either the Moxun, or the Hexbeam.

I’ve seen the Hexbeams adertised as being suitable for a light duty rotator, so presumably doesn’t exert too much load. Also gives me multiple bands. The down side is that it has about half the gain of the Moxon & the front-to-back isn’t as good.

I might go for the Moxon but I think a bit more reading through the specifications is required (with regards to the windloads) before I make a final decision!!!

In your case, I would consider this antenna:

https://www.spiderbeam.com/product_info.php?info=p6_Spiderbeam%2020-15-10m%20HD.html&XTCsid=3089b7630d3611680fc553f72c0e43f4

I have had this antenna for many years. The results have been very good. Good luck !!

Hi,
I’ve had 1 to 6 element HF antennas over the years all on a 40 ft tower and as you might expect:

1 A monoband yagi is better than any multiband or compact beam for the same number of elements…

2 Bigger is better. Gain is proportional to boom length. A small turning circle, ie short boom and bent or loaded elements means lower gain.

If you want to work real dx (12,000 + km) then don’t compromise. Go for a 3 element monobander. (you said you aren’t interested in other bands). The turning radius will be about the same as for a 2 element but the extra gain and directivity is important. Having a narrower beam means less noise and hence a better ability to hear the weak ones. The extra gain means you hear better and you will be heard better. Crank the mast down when wind gusts are going to exceed 80 km/h or whatever is going to be safe.

I currently use a beam that is 2 elements on 20, 15, 10 m and 1 ele on 17 and 12 m. For a small compromise antenna it works pretty well. I chose this for light weight, fairly low wind load and 5 band capability.

Small compromised beams may seem to work pretty well but until you have used a big yagi you don’t appreciate what you loose in short boom multiband beams.

Good luck.

73
Ron
VK3AFW

1 Like

HI James

NO match for the WARC bands though that Spiderbeam … shame that.

Have had around 10 different beams over the years. Home brew single band yagis, Linear loaded and wire (Hexbeam), and a big Log Periodic which wore out after 10 years. Force 12, Jaybeam, Sommer, Tennadyne T10 LPDA, Optibeam, Hexbeam (South Wales guy who sells them - long waiting list - other makers available). All beams were chosen to suit my situation, the mast I had at the time and what I could get planning permission for. The Optibeam was by far the best and was by far the heaviest, the 11-5. I was a serious DXer then and the 11-5 put out a serious big signal from 2011-2017. Your mast will not safely and reliably accommodate that weight. Your turning radius will not accommodate a Log Periodic for 20m and up. If you need WARC bands and your main interest is SOTA then you need something like the Hexbeam. It will still work a significant amount of DX - expecially on Data modes like FT8, FT4 and CW. The aerial has a small turning circle and is light compared to an aluminium yagi. They will perform better as will a quad. But most people who build quads find they need constant atttention and break. The Hexbeam with wind struts fitted is unlikely to fall down or break. My Hexbeam when erected JUne 2018:

I would suggest you look at the SOTA Chaser database logs on 20m and up of the hams who make these suggestions and see what they have worked with their current antennae. It could give a clue as to how useful their aerials are! I have used a Hexbeam for the past 14 months, its not a high gain antenna but it’s adequate for my current needs and no worries about it falling down. I haven’t had to touch it since it went up 14 months ago after 15 months of planning wrangles and an appeal which I won.

Is this antenna for the remoted station you asked loads of questions about some months ago I wondered?

73 Phil

PS Just read the advice from Ron. He’s right on all points and is like me, speaking from experience. If you want top performance on a single band go for a yagi as he suggests as big as your mast can safely accommodate without it falling down.

PPS Oh I forgot to mention - I also had a G4MH Minbeam in 1983, my first beam. It seemed good on 10m but was like a rotable dummy load on 15m and 20m. Buyer beware and don’t believe the gain figures quoted on antennae marketed for the hams!

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That’s partly the reason why I asked on here to see if I could get any first hand experience from people, because I know that the manufacturers often “fudge” the figures slightly!

Unfortunately not. I did have the remote station up and running for several months. It was quite successful and I had a lot of fun with it.

As I suspected at the time, the downfall was the security. I tried to be as discrete about it as I could but theres only so much you can do to hide a guyed mast supporting an antenna system mounted 10m above the ground in an open field!!!

I went down there one day to cut the grass & noticed a couple of people snooping around. I got cold feet & decided to remove the system, which turned out to be a very good move). I needed to take the kit home for maintenance anyway.

I went back a week or two later & someone had been in there & broken into the cabinet (where the radio equipment would have been if I had left it there).

They stole an electric fence power supply and the solar panel that was driving the electric fence (although curiously they left the leisure battery behind).

After that I didn’t have the courage to leave any kit unattended!

As you ask though, the noise at my home QTH seems to have dropped slightly from what it was (which was the main driver for wanting the remote system in the first place).

I am also having some ground work done at home and am taking the opportunity to bury a large quantity of wire radials (whilst the garden is being dug up anyway).

The slight drop in local noise, coupled with a much improved ground system & a significant qunatity of ferrite chokes on just about everything in the shack seems to have made working from my home QTH a bit more manageable.

That said, I still intend to set up the field for daytime/overnight stays (operating from my caraven) if I want to play on 80m or 40m.

I’ve measured up & reckon that I can definitely squeeze in a 4 square system for either 40 or 80. At a push, I might just squeeze in a 4 square for both bands!!!

SpiderBeams make a nice 12m mast (I currently own one which I use as a 1/4 vertical on 40m). It fits nicely over a 2" scaffold pole.

My plan is to bury the radials & coax cables. I can then have 4 posts (concreted into the ground) which I can slide the fibreglass poles over the top.

When I’m not there I would remove the masts & the controllers.

SpiderBeams do a larger pole around 20 meters tall (which requires guying), so could possibly get an 80m square in the field for night-time DX from the caravan?

The idea is to have 20m at home, then go to the field if I want to do any serious DXing on 40 or 80.

Obviously a 4 square isn’t as good as having a beam on a tower, which I’m never going to achieve on 40 or 80 with the space & finances available, but most figures seem to suggest around 5-6 db gain with a FB of around 20-25db (which isn’t bad. They are also low angle, so I should be able to do something with that!

Thank for the feedback on the remote idea you had at your field.

Sorry to hear about the security issues at your field, and the theft. There are 20,000 fewer police in England & Wales now than there was 10 years ago, especially in rural areas, so there is more crime. Still a nice spot to go to with your attended caravan though…

A deteriorating society unfortunately does not help, so I can imagine it is back to the drawing board for you.

A better antenna on 20m and up will increase the signals in and out and reduce the interference you experience from your neighbours equipment in some directions. A little gain in the right direction from a rotable antenna above house roofs and your interference from devices could dissapear completely - however it may also increase if you are pointing the direction of the radiated “smog”. Spend as much money as you can on good quality coax for 20m and above and protect it well . I use Ecoflex 15 and it is now 12 years old having been fitted at 2 different QTHs. I also have two runs of this buried to a tree in my garden inside ducting. No issues, well worth the work in putting it in. I bought a 100m roll. If you spend a lot of £££s on coax it pays to shroud it in flexible plastic conduit. Cable like this is not meant to be winched up and down on a mast as mine is several times a week, so it is necessary unless the aerial mast is fixed.

One can but dream about 4 squares and rotatable 40m and 80m beams… you don’t need them unless you want to work over 300 DXCC Countries on either band. More trouble and expense than they are worth, unless you are really serious about DX or winning an International Contest. To get the best out of them you need to stay up all night and retire to bed during daylight.

You reap what you sow and putting out a respectable signal is down to how much effort, in getting planning permission in the UK for big aerials and the work involved in installation and set up. Family members may not be favourable in your efforts to improve your antennae and your neighbours may ostracise you in the process. You have to decide how important your hobby is to your life in the end! Good luck anyway whatever you decide to try.

73 Phil