Komunica HF-PRO-2-PLUS-T HF loaded vertical.

A New antenna under review–the Komunica Power HF-PRO-2-PLUS-T

It is a constant search in amateur radio to find the “best” antenna.

But what does “BEST” really mean?

Yes, it could mean the highest gain, lowest noise antenna and for that, the amateur spends thousands of dollars on a tall tower and enormous beam antenna or multiple phased beams.

But what about the rest of us that don’t have either the land or the money to set up such a great antenna. “BEST” to us means the best we can manage within our budget.

What if we are in a home location where there’s no chance to put up a HF antenna at all and we have to go out portable – or we prefer to operate portable, from a park, from a summit or from an island. Now other things come into consideration, such as size and weight and if operating alone, can the antenna be put up by one person? If it is an antenna using a mast, how will the mast be supported? Is there enough room for guy ropes?  If we want to keep things really light – we just want to throw a wire in a tree – what if there are no trees or the park warden doesn’t allow that?

The “Best” antenna depends upon the situation and if we are talking portable operation going somewhere we haven’t been before, we have to have an adaptive answer that doesn’t rely on a fence post or trees to be available to support a mast or wire antenna.

At best the antenna should work on more than one band as we never know how radio conditions will be and switching bands may make the difference between making contacts and not.

Talking of conditions, weather can change quickly when you are miles from anywhere in the countryside or up a mountain, so an antenna that can be taken down and packed away quickly would be a good idea.

So, let’s define our needs for a portable antenna,

  1. Small to carry,
  2. Light,
  3. Self-supporting,
  4. Multi-band without needing an ATU,
  5. Reasonably priced,
  6. Quick to put up and takedown.

If you ask 5 portable operators, you will get at least 7 different answers between them – but does any one answer fulfil all of our needs?

 Here’s a brand new one that does – the Komunica HF-PRO-2-PLUS-T HF & VHF loaded vertical which I have purchased based on my good experiences with its predecessor. This is my review and my experiences – as always YMMV.

Some of you may have heard of the basic HF-PRO-2 model which I have used for a couple of years. This new  “-PLUS-T” model has the solid radiating element replaced with a telescopic one. This improves on our points 1 & 6.

The antenna itself is designed to fit a SO-239 socket and so can be used “static-mobile” on a magnetic mount on top of a car, if that’s the way you go portable or it can be used with a small tripod and radial wires – which is also available from Komunica or you can do as I did and took an unused photographic tripod and converted it by adding an SO239 socket and 8 3 metre long radial wires. (adapting your own tripod, of course, helps our aim number 5.).

Another difference with this new model over the basic HF-PRO-2 is that the parts are simply screwed together by hand rather than using an Allen key – this fact alone will pay for itself when out on a mountain top in driving snow with gloves on – trying to find a dropped Allen key in the snow is not fun! 

The HF-Pro-2 covers 40m – 10m plus 6m.

The HF-PRO-2-PLUS-T is sold as covering 80m & 40m through 10m plus 6m and 2m. In fact, it will also cover 8m (40-44MHz) and 4m (70-71 MHz) as well. It gains coverage of 80m and to some extent 60m by using an add-in coil, that again is screwed into the antenna by hand. The bands above 30MHz are obtained by adjusting the length of the telescopic antenna element.

The amazing thing about this antenna is how small the components are when taken apart. You can lay the main loading coil body, the 80m coil and the telescopic element alongside each other easily on a piece of A4 paper.

When assembled and extended though – as you can see, there is very little difference in size between the HF-PRO-2 and the “PLUS-T”:

 

 

 

 

 

 

 

 

 

 

 

 

 

The Komunica HF-PRO-2 is on the left in all of these three pictures, the PLUS-T on the right.

Which of these sets will fit inside your small backpack??

While the HF-PRO-2-PLUS-T covers VHF as well as HF. The use on VHF (8m, 6m, 4m & 2m) is purely by using the telescopic sections adjusted to be a ¼ λ (8 metres and 6 metres) or a 5/8 λ (4 metres and 2 metres) whip and you can expect an SWR between 2 and 2.5:1. Still usable and it does avoid taking another antenna to the summit for these bands but the antenna’s primary bands are the HF ones where an SWR around 1.5:1 can be expected. The exception to this is 60 metres where again an SWR over 2:1 can be expected. To be fair to Komunica, they do not sell this antenna as a 60-metre antenna, rather a 40 metre to 10 metre one with 80 metres supported by adding the extra loading coil. With 60 metres, it’s a case of, if you don’t have a better 60-metre antenna with you and you need to operate on the band, this antenna will work.

Generally, for its small assembled size, the antenna performs well, making contacts around continental Europe (east & west), and into the UK and Scandinavia. Reception of stations from the US and Australasia is possible on 40m at present (October 2020) but so far, I haven’t made contacts with these DX locations using this antenna. Perhaps as conditions improve as we move into solar cycle 25 and 20, 17 & 15m open up again, such contacts will be possible. 

To meet all of our listed requirements for a portable antenna, there has to be compromises and only you will know whether the performance of this antenna is good enough for you or whether you prefer to have the better performance of a full-sized single band or linked dipole and are happy to carry the needed support mast. One thing is for sure, this antenna is small enough to have inside your backpack with a small tripod and radial wires teamed up with one of the small portable rigs with their internal battery like the Yaesu FT-818, Elecraft KX-2 or ICOM IC-705 and you have a portable solution with you “just-in-case” you have time, or need it unexpectedly that will perform well.   

Is this the “BEST” portable antenna solution? As always it depends on your personal needs but for me, for weight, size, price and performance, it’s the best I know of at the moment.

73 & work you on the bands!  Ed DD5LP.

Antenna in use:

  1. On car (using a magnetic roof mount):
  • Testing and recording settings on a tripod in the garden:

VK2JI – SOTA in VK2 – 20th. November evening activation of VK2/HU-093 (Mt. Elliot)

Preparation:

Following requests from several European and US amateurs for VK activations outside of our normal daytime schedules, several activators have been activating in the evening to give the DX chasers a chance and to take advantage of better propagation.

Unfortunately for me, the only summit that is in reasonable traveling distance from where I live is Mount Elliot which I have activated more than once before, so there would be no points in the activation for me or for Rod VK2LAX who agreed to take part in the activation as well, unless by chance we got a summit to summit contact. So this activation was for the chasers and to have some fun. I also used the activation to try out a new antenna I had bought a couple of days earlier, a Diamond RHM8B which appeared to work a lot better than expected.

As it turned out we got no S2S contacts but I worked both into the Cook Islands (thanks Perrin) and into England (thanks Don).

As well as many of the normal chasers / activators across Australia, Rod also bagged his first ZL SOTA contact and worked into Germany, Switzerland and the UK. So it was an enjoyable evening.

Despite this summit being close to a city, it still has Aussie wildlife and we were warned to watch out for leeches while walking down a trail that goes down the escarpment that we take to be able to exit and re-enter the activation zone because the car park is within the activation zone.Leeches were not a problem but “dive-bombing” Christmas Beetles were when it got dark and we were the only light source for kilometers!

Pictures:

Diamond RHM8B antenna on FT817ND

Diamond RHM8B antenna on FT817ND

Operating position at dusk

Operating position at dusk

Night time operating in the dark 1 of 2

Night time operating in the dark 1 of 2

Night time operating in the dark 2 of 2

Night time operating in the dark 2 of 2

Video:

Rod VK2LAX operating as it got darker, and, darker ……

Stations worked by Rod VK2LAX:

(40m) Peter VK3FPSR

(40m) John VK2YW

(40m) Marc VK3OHM

(40m) Paul VK2KTT

(40m) Marcel VK2HAQ

(40m) John VK3FMPB

(40m) Ian VK1DI

(40m) Al VK1RX

(40m) Lamont ZL2ALK

(40m) Peter VK3PF

(40m) Mark VK3YN

(20m) Bert DF5WA

(20m) Don G0RQL

(20m) Matt VK2DAG

(40m) Paul VK5PAS

(40m) Matt VK1MA

(40m) Andrew VK1NAM

(20m) Hans HB9BHW

(20m) Damian M0BKV

Stations worked by Ed VK2JI:

(20m) Ernie VK3DET in Ballarat

(20m) Perrin VK3XPT operating as E51XPT on vacation in the South Cook Islands

(20m) Don G0RQL in Devon, England.

(12m) Matt VK2DAG on the Central Coast – this was my first contact on 12 metres from a SOTA summit.

22nd. June – Further Antenna Tests at Mt. Elliot

Test twice – use once.

Following the work on the end-fed wires in the back garden, the time had come to try them out on a summit. So with Jim VK2LC, Col VK2ZCO, Rod VK2LAX and Graham VK2GRA, it was off to Mount Elliot again. As I have said before, this is a very easy summit to get to but will probably be the only SOTA classified summit within 2 hours driving time for those living in the southern part of the NSW Central Coast. It has the advantage of many options to support an antenna – trees and bushes abound as do wide open areas where squid pole based antennas such as my 40m horizontal loop antenna can be erected as I did on my last visit here. This time however I was looking for the most simple of set-ups for the end-fed and found it in a small area of grass and bushes where I simply laid the antenna out, touching the plants between 1 and 1.5m off the ground. Jim had brought a tripod based vertical antenna along and local reports gave it about a 1 S-point advantage  which given its extra height is not surprising. That antenna wont fit in a trouser pocket as my full set of HF band end-feds will though.

The highlight of the day was hearing and then working Andrew on 40m SSB who was operating as VI100ACT from VK1/AC-018. He was a good strong 5-9 signal and came straight back to my call of just 5W into the end-fed antenna from the FT-817.

The “lowlight” if we can call it that, was that the the rig started cutting out. At first I suspected the use of the rig on the 20m version of the end-fed had caused this perhaps because of a bad VSWR but it turned out simply to be that the battery had discharged. I had forgotten to charge it up since its last outing and to add insult to injury, the rechargeable AA cell battery pack that I had brought along as backup was no better. It later turned out that 4 of the new 8 NiMH cells were faulty and not holding charge.

I can hardly believe myself how well the end-fed laid simply on bushes works – for the ultra-light QRP portable station, this is definitely my recommendation when teamed-up with a very small and light antenna coupling unit – I use the one that is part of the Chinese version of the Miracle Whip that I bought.

Here are a few pictures illustrating the set-up at Mt Elliot.

A short video is up on YouTube at – http://youtu.be/crvdx5xn98U

 

Operating position - FT-817 antenna tuner and wire antenna on a fold-up chair.

Operating position – FT-817 antenna tuner and wire antenna on a fold-up chair.

Wire antenna leaving operating position over chair arm.

Wire antenna leaving operating position over chair arm.

Wire antenna simply drapes over fence and into bushes.

Wire antenna simply drapes over fence and into bushes.

Antenna laying simply across the top of the grass.

Antenna laying simply across the top of the grass.

15th and 16th June – Antenna Tests

First failure, then success.

Following a disappointing first test of my end-fed 40m wire antenna up at a local high-spot on Saturday 15th. (I could hear all very well, but no one could hear me!) some re-thinking and investigations took place overnight. I found differing lengths specified for the driven and counterpoise elements on the antenna from different internet websites. My feeling was that the antenna was not resonant but the “miracle antenna” auto-transformer ACU was matching it to give a good VSWR to the rig but the antenna was not radiating well as would be the case if the length was wrong.

I measured off wires to the new lengths (19m driven element and 10.5m counterpoise) ready for testing on Sunday 16th.

I laid out the antenna simply over bushes in my back garden – about 1.5m above ground level. Testing first of all using a Rig Expert antenna analyser I had to extend the driven element another 3m before resonance came down to 7.1MHz.

I then attached the FT-817ND to the ACU and antenna and listened around – again receive working fine, but what about transmit? First I called a strong local station – Bill VK2XT and although I was a relatively weak signal, I managed a nice QSO with this great gentleman who has been licensed for over 80 years.  As I now knew I was getting out I was more confident and when I heard Ron VK3AFW/P up on VK3/VW-009 calling CQ SOTA – I thought “give it a try” and sure enough Ron came back and we exchanged 5-4 reports in both directions. Later I was also able to call and work Marshall VK3MRG/P on VK3/VN-027. It’s really amazing what can be worked running just 5W at each end and very simple antennas!

Here are a few photos of the very basic antenna set-up (click on the photos to see the larger format) – the thin red line you can (hopefully) just see in the pictures is the AWG24 wire wrapping wire (usually used to patch connections under printed circuit boards).