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The Big Antenna Question

This article got a follow up on 27/07/2018 – link

Abstract: what should I do?

ON5ZO operating profile:

  • Main goal in amateur radio: work DX in CW. Either on the contesting bands as well as on WARC.
  • Most of my contacts are made in the contests but I do appreciate casual DXing and ragchewing.
  • Try to generate pile ups (yeah right, in ON) rather than breaking them. I have given up the DXCC chasing and stay clear from the moron induced mess when a rare one pops up.

Here’s the deal

Since I find myself on the regular bands for more than 90% of my time in the contests, I like to hang out on the WARC bands outside of the contests. The 30m band is my favorite. A simple CQ with any simple antenna brings truckloads of DX from all over the world. Often at the same time. It seems that 10.1 MHz almost always works.

Until 2011 I had a tribander and a WARC trapped dipole above it. That WARC dipole did a great job given its simplicity and size. I was often active since I had immediate access to 30/17 and 12 which was pretty much closed between 2004 and 2011. A dull week night, an hour to spare on a weekend without a contest – a few quick contacts were logged on WARC. Anecdotal evidence: I installed my brand new tower and my first real antennas and my very first QSO with that was NL7G on 12m. Late 2004, 100W.

But somewhere in late 2010 a trap blew and I found myself without a permanent WARC antenna. The good thing was that OT1A offered me the most important parts to complete a 40m dipole. I put that above the tribander and my 40m rates and scores went through the roof. Another proof that a good dipole at reasonable height kicks butt. In that respect, the new antenna was an asset.

But soon after I started missing my WARC antenna. I made a simple parallel wire inverted V and hung that on a low band pulley. That worked fine for what it is. Even with a sharp angled apex. Even when not too high. The problem is that I need to take it down for a contest because the pulley is used for the low band wires. And then after the contest, back up goes the WARC wire antenna. I got so fed up with that field day routine I just didn’t bother anymore. A direct result of losing easy access to the WARC bands was that I just wasn’t active anymore between the contests. Later on I converted the remaining half of the WARC dipole to a ground plane with the inverted V triband antenna as a set of elevated radials. That worked as in “resonant in the band with very low SWR”. That didn’t work as in “hear and work DX”.

And now I’ve had it. I feel I’m missing out on a lot of fun and I don’t enjoy the hobby as much as before. So I need to fix this and regain access to the WARC bands without an extra antenna. But how? I have given this a lot of thought over the last two or three years.

What do I (not) want?

  • All I have now (40 > 10 on the tower) but with WARC included. Six meters is a bonus but not a priority. I don’t want big and heavy antennas. It shouldn’t take too much wind and needs to be as stealthy as a tribander on a tower can be.
  • Price is not an issue. By which I mean that if a certain solution costs more than a comparable outcome, I am willing to pay for it but only if it makes for a better antenna system in any way.
  • I do not want to end up with less performance on the regular bands.
  • I do not want more mechanical load on and visible impact from the tower. ‘Less is more’ does apply here. Full size elements for 40 are out of the question.

The technology of the so called dynamic antennas is appealing. They’re quite small and cover all the bands with three or four elements. That is my self-imposed limit when it comes to size. However I see many more possible points of failure. I’ve said it before: I’m a glass-is-half-empty-guy. Apart from the usual things that can go wrong with an antenna, this dynamic technology has much more to it than an aluminum tube. I don’t even include traps into the equation as well as complex loading systems à la KT34XA.

  • There is much more wiring to it. Wiring can break and the outdoor connections must be kept dry.
  • Stepper motors are quite robust but can fail.
  • The conductive ribbon can break or jam in the fibers.
  • What about the gears and sliding mechanisms?
  • What about the feedpoint where RF is applied to the sliding ribbon? Will the movement of the ribbon against the feeder cause it to wear out?
  • The controller’s electronics can fail. A normal yagi does not have electronics.

There are two major brands for these antennas. The pioneers SteppIR. The Italian copycat is Ultrabeam. There is also the obscure dynamic-antenna. They have a website but I can’t find any references.

There are many happy users for both brands. There are also many horror stories (like here and here) documented with epic fail pictures for both brands.

I know that OT1A has been a happy SteppIR user for almost ten years. Another trustworthy Belgian technically skilled  operator has told me his only regret was not having bought his UltraBeam tribander sooner. Another local ham whose opinion I trust said that his UltraBeam is a quality product yet dealing with the company to solve an issue has been cumbersome. I once sent an enquiry to UltraBeam and got no reply. After two weeks I resent the same message to get the brief answer to ‘keep an eye on the website’. That doesn’t build my confidence in them. I demand customer support Elecraft style. That too is worth a few more Euros.

What do I have now?

An OptiBeam OB11-3. Modest tribander on a 6m long boom but it works very well. It has 3/3/5 full size elements on 20/15/10. On top of that there is the OptiBeam shorted 40m dipole. Those who follow my contest adventures know what this simple setup is capable of.

Situation on the tower NOW: 32kg / 0.84m²  (tribander)  +  11kg /  0.31m² (dipole)  =  43kg / 1.15m²

The OptiBeam solution

I’m very satisfied with the OptiBeam products. They perform very well and the quality is superb. Also the company owner is very responsive and helpful. Just for comparison I studied the available models to add the WARC bands. With as many elements per band as I have now but without going to a much bigger and heavier antenna. This is the outcome.

  • OB11-5  (3 / 3 / 3 / 3 / 5 elements 20m>10m)    45 kg          1.47m²       1.799,00 Euro
  • Dual band dipole OB1-4030   14kg   0.45m²   739 Euro
  • Optibeam solution: five band yagi and 40/30m dipole. Total: 56kg / 1.92m² / 2538 Euro

Cheapest solution but heaviest, most wind load and most visual impact. Exactly what I DO NOT want.

The steppIR solution

The SteppIR antenna that covers my needs is either the DB-18 or DB-18E. Both have three elements on a 6m boom. The difference is that the E model has 3 trombone elements (2L on 40, 3L on the other bands) and the plain model has only 2 trombones and one plain element (2L on 40+30, 3L on the other bands).

  • DB-18     41.2kg      0.9m²    3980 Euro
  • DB-18E    45.3kg    1.1m²     4960 Euro

There is a difference in numbers between the SteppIR website and the specs on the German reseller’s page. I should get the exact numbers confirmed.

I think that 1000 Euro does not justify one more element on 30m. Coming from nothing, a two element yagi on my favorite band (30m) as well as on 40 should be something special. Might as well be that two elements wider apart work better than three closer to each other. But how to determine this?

The UltraBeam solution

At first my plan was to buy the UltraBeam UB40MX. That seemed nice and covers my needs. However with 15m wing span it has quite long elements. Being a single antenna with 1.15m² wind load, it is still quite heavy (63kg).

But a while ago UltraBeam released a new type of folded element yagi. The folding is done in the vertical plane instead of the horizontal plane. Maybe influenced by the Despole design? I have made a number of wire antennas where I fold back part of the antenna or just put the ends in the hands of gravity to make it fit and the principle has always worked.


Currently UltraBeam has two models available.

  • Yagi UB640 – VL1-3   4.86 boom    29kg   0.77m²       2650 Euro
  • Yagi UB640 – VL2-3   4.5m boom    35kg   0.97m²       3450 Euro

These two models are lighter and shorter than the SteppIR model. And quite a bit cheaper. And UltraBeam offers FOUR year warranty. And as another Belgian UltraBeam owner said: “It takes a day’s drive and you’re at their front door”.

The model with two folded elements has my preference. That means two elements on 40/30 and three on the other bands. I noticed that the boom is 1.5m shorter than the SteppIR. However, assuming the SteppIR folded trombone elements are 0.5m apart, this would save 1m if you put them in the vertical plane.

EA6NB has this antenna (see it here). It looks weird with the pale fibers contrasting against the blue sky. Especially with the black marks that breaks it into smaller pieces visually. I can’t say that this is a beautiful antenna. Not that this matters, it should be strong, everlasting and perform like a champ.

An extended version is expected with 4 elements (3 folded and one straight?) making it 3 elements on 40/30 and 4 on the other bands. That would actually improve the number of elements on all bands. The question is: what will it cost, what will it weigh, and will this antenna be noticeably better on the air than its smaller brother? But the real question is: can you trust the gain figures as stated by the manufacturers? I don’t know. And how to evaluate then?

Now what?

It took me almost four A4 pages of text to list my thoughts and options. I have been thinking about this a lot for almost two years if not more. There is of course the financial aspect (investment) but what bothers me more is the work. I simply hate doing tower work. Even with a tilt over tower. On the other hand, having all bands on a single antenna, it’s quite appealing.

What should I do? What would you do?

This article got a follow up on 27/07/2018 – link

5 replies on “The Big Antenna Question”

Yo Franky …. little DX on 160m this morning so I was reading your homepage 🙂

Personnally I wouldn’t spend 5k on an antenna with a lot of moving parts … yes, I do have a SteppIR in my setup but we inherited that antenna from the PI4TUE station. It is about 10 years old now and currently is working w/o any issue. And I must admit it does have nice features (180° / bi-dir) but still … if I would have to buy a new antenne myself I don’t know if that would get through the selection process.

Of course there is always a trade off (as every antenne is 😛 ) … I love how the Optibeams are build and perform and perhaps the OB15-7 would be a good alternative. But that would perhaps leave you with a beam that’s a worse performer on the contest bands.

Looking at my contest station setup (MS / M2), a multi band Optibeam could (with the correct filtering) always be used by 2 radios on 2 different bands …

Also to consider is the noise a SteppIR makes when changing bands/tune. If your neighbours live close this could be a no-go.

I never really thought about it to be honest since the WARC bands don’t have my main interest at this moment. Due to time limitations I focus on HF contesting. 12/17 is covered by the SteppIR and 30m is the only band I don’t have an antenna for but just to catch some DX I have been thinking for some time now to put a simple dipole for that band (I don’t have ANY interests in the newer bands like 4m and 60m).

my 2 cents 🙂
73 Frank ON9CC / OT6M

You are 100% right about this one. I’ve been soliciting user input and contemplating even more about this. An update is in the works, stay tuned.
Thanks for your views on the matter.

73 and may your log be full of (160m) DX in 2016!

Dag Franky
k hebuw bedenkingen een beetje laat gelezen, ik heb reeds dezelfde overwegingen gemaakt maat toch weerhoudt me iets om motorisch gestuurde elementen te monteren op mijn mast, wegens prijs/onderhoud/… .
Ik wil u mijn volgende ervaringen meedelen ivm met de cushcraft x7 , mechanisch is deze ant. zeer goed gebouwd, ze werkt uitstekend op de klassieke banden.
Voor de warc banden gebruik ik dezelfde ant, de swr is wat hoog maar toch alles wat ik hoor werk ik en er is een richtingseffect, dit dankzij de log periodic cell.
Voor 40/30 m heb ik een optibeam dipole er boven staan, dit werkt super.

De kwaliteits/prijsverhouding van dit systeem valt mee, de windlast ook

mijn beste wensen voor u en uw dierbaren

73
Dirk

Hi Franki,

I must say i am quite interested in this article as i am currently trying to get information on the VL2-3 which is quite of interest for me. I do not see many ham having this one. I currently have an OB9-5 which is an excellent antenna on a 5.1m boom, this is the max boom length i can use at my place due to space restriction.
Going for a 3 elements instead of 2 of the OB9-5 with a boom shortened by 60cm is really interesting. Same goes for the 180 degres function which is also nice.

I will lose of course the ability to use the OB9-5 on multiple bands at the same time with the triplexer of 4O3A but i am really considering it to add the 40M and 30M band in my setup and increase to 3 El.

If you have more information thanks to share 🙂

Hi Greg
Thanks for your note.

I’ve been planning an update and follow-up but I just couldn’t get myself to write it.
Bottom line is that I probably will leave things as they are and not install a ‘dynamic antenna’. There seem to be many problems with the motors, ribbons and guiding mechanisms for both brands. I admit there are many happy users too without a problem.

The one thing I’ve been seriously considering is trying to add 30m to the 40m dipole. Or replace the 40m monoband dipole with a 30/40 dual band model. 12/17m are goners for a few years and the according wavelengths are manageable for something small with wires.

Right now the antennas and rotator are under serious pressure since last night. High average wind speeds and very strong gales for hours on end and still no end in sight. The aluminum tubes are flexing but so far everything is still where it should be.

Stay tuned…

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