Thanks Ed that is useful. What was interesting is that in the damp soil the SWR curve was different to tests in dry soil, so the stake would be different to using a tripod. In dry soil the curve was more like a squared off U. In wet soil the shape was more like an inverted bell curve. I suspect the ATU is working harder in dry soil. When it gets a bit warmer I will do more testing. I have just bought a VNA.
Ed
Thanks for the update
Another example to debunk the on going theory of “hamsticks they dont work” for SOTA or POTA.
The dipole pundits are fuming right now as you just needed a stake in the ground to get on air quickly
John VE3IPS
I am a bit of a linked dipole bigot but own too many Hamsticks as well. Next outing will include my Outbacker Perth
As a result of that original thread about hamsticks I bought a 20m with a mag mount to use on a vehicle. I was unimpressed by the SWR at first and at the time I didn’t have an ATU. After the first initial disappointing trial I gave it another go a few days later and while getting it out of the bag discovered what I thought was just a label were the folded up instructions! These told be the length is adjustable and you are supposed to er…adjust it. 
I then got the SWR down to about 1.3:1 without an ATU.
I think the main problem with it is the length and weight but for the price it does a good job.
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I know they are heavier than my Bandspringer, but in the wind and cold yesterday I was reluctant to mess about with guys and a SOTA pole. I have three options now. The Hamstick, Bandspringer and 3 band vertical 20/30/40. When it gets warmer I plan to do some side by side comparisons. For a quick ‘run n gun’ activation it worked well. It was great to be out again!
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Yes, side-by-side comparisons are the only way, ultimately.
Another technique that can be deployed, but strangely overlooked by many, arguably most activators in the SOTA programme, is to make use of the activation zone rule. This allows you to set up anywhere in the contiguous area down to 25m vertically below the summit.
On many hills, depending on wind direction and topography of course, this allows you to set up in considerable shelter. On the big European SOTA Day back in September, the wind would have absolutely trashed my fibreglass masts and wire antennas on the summit of Shining Tor G/SP-004, but as the prevailing wind was mainly north-easterly, I was able to set up under the cliffs looking out over the Macclesfield Forest, and have an “antenna farm” up all day (though camping and sleeping on a slope was rubbish - lesson learned there!)
Dipoles and groundplanes are more efficient than hamsticks, but less versatile in challenging weather conditions.
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This is shaping up to be an interesting thread.
Some activators want ultimate Dx, some want to qualify the summit before freezing up. So there’s no one ‘ideal’ antenna solution.
This could get like the old myth about the Sixties where you had to be either a Beatles fan or a fan of the Rolling Stones but not both [I was both]. I’ve used linked dipoles [usually in inverted V config] and EFHWs [horizontal or sloper] happily for years but very recently I have also become a fan of my new [Cha MPAS Lite] vertical for its quick & easy deployment, small footprint and ruggedness in high winds. I’ll select a wire antenna or the vertical depending on circumstances for each activation on the day.
I know how you feel. Not much extra weight in my case …
I’m sure you’re absolutely right for the lower HF bands but my limited A vs B comparisons with my vertical [not a hamstick] suggests that on 20m it can go either way. I field-tested my MPAS Lite in that stormy weather we had a few weeks ago on my local SOTA summit. The wind was going right through me and the 17ft [5.2m] long telescoping whip was bending at the top but the whole thing seemed very stable despite gusting.
My homemade groundplanes ARE verticals. I use dipoles for 80-60-40 and verticals with groundplane for 30-20-17-15-12-10.
That {wavelength} split is fast becoming the dominant factor in my choice of dipole vs vertical. I know I could make the vertical more efficient on 40m and 60m by deploying multiple counterpoises rather than just the one. But if I were to go to that extra trouble, I might as well erect my 6m pole and wire antenna.
I think the best antenna in any situation is the one that goes up, stays up, allows you to make enough contacts to be satisfying and packs away readily to allow you to complete an activation.
Sometimes there are more options than others. In high wind and very low temperatures, the choice of a compact vertical that was quick to set up was ideal. There are plenty of others huddling at home wishing they were on a hilltop.
Well done, keep it up.
73 Andrew VK1DA/VK2UH
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I use vim on summits. I’ve never gotten any DX with emacs.
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I’ve had Qs sitting on Maine and NH summits from Oregon to Germany with hamsticks on 20 and 17 and 2 radials. Even had this oddity, Namibia:
MB
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You probably haven’t configured it correctly. You’ll need some Lisp macros in your .emacs.d folder for working DX.
It’s hard to do CW when you’re holding down a seven key combo
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Have you posted any details on this Tom? It would be interesting to see.
They are the easiest aerials to build Martin, and incredibly effective. I’ve worked the world on mine including loads of DX, with 5 watts from an 817. They pack really small and are lightweight, and you have the satisfaction of knowing you’ve built the antenna yourself.
I’m not at all practically skilled, so if I can make them, anybody can!
Basically:
Cut four lengths of wire to quarter wave for the band you want. Thicker wire is better as it is stronger, and offers a greater bandwidth. The heavy duty green military spec from SOTAbeams is my wire of choice.
Connect three of the wires to the outer (braid) of coax feeder. Connect the other one to the centre (core) of the coax.
To deploy:
Hang the driven element (connected to the core if the coax) from the top of your mast (fishing pole). Acrylic isolators from SOTAbeams are good for this. Secure the other three wires to the pole, just below the feedpoint, with a reusable cable tie.
These three wires form the groundplane, and are also what you use the guy the mast. At the ends of the radials, add a length of nylon cord, with a loop at the end for pegging.
And there you have a highly effective antenna that you made yourself, cost very little and weighs less than your packed lunch.
I’ve made them for every band 30m through 6m and had fantastic results with all of them. I get all the bits from the firm mentioned above (that I don’t mind recommending now my mate isn’t running it!) - wire, coax, top end isolators, nylon cord, reusable cable ties, antenna bag, wire winders, lightweight pegs, telescopic mast.
If you fancy a socially distanced joint activation, I can show you one of mine and prove all the bold claims above!
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Thanks Tom I understand the concept. I will try one for 20m. As soon as the weather improves I plan to do a big test session. I have a Bandspringer and also a tunable vertical 20/30/40 I have built. I enjoy the tinkering/building side of the hobby.
A joint (distanced) activation would be great, as soon as the weather improves. I have yet to do The Cloud! I am waiting for my second jab, so watch out world!
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Having played a lot with multiband antennas - linked dipoles or end-feds with tuner - over the years, I very much favour single band resonant antennas. A single band is usually more than enough to keep you engaged for a typical stay of say one hour on a summit, and the performance plus lack of “flaff” is way better!
You’ll have a lot of fun with a 20m GP, especially if you have CW and FT8 in your operating repertoire. But even with just SSB, a GP is the best way of working DX with QRP.
That isn’t how impedance matching works. Is it true that some power is lost in the ATU, but that is only because the inductors are not perfect inductors and the capacitors are not perfect capacitors. There are some resistive and dielectric losses. But an ATU made of inductors and capacitors does not magically absorb reflected energy and somehow turn it into heat. An impedance matching network made of pure inductors and capacitors is lossless.
Martyn M1MAJ
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Well done and thanks for sharing. I would second M1EYP’s advice about using 25m rule. I usually set up just off summit for two reasons: stay out of other people’s way and to shelter from prevailing wind. Good idea to have an easy/quick option like the Hamstick. At the end of the day, if you get the contacts logged, it’s a good antenna. I did expirement with a quick deploy 20m coil loaded vertical last year for similar reasons (still need more field time to properly assess) and current project is a super-lite quick deploy mag-loop.
Had a play today with a similar setup to Tom (M1EYP). It was a sunny still evening. Probably need to extend the guys to bring the radials a little higher at the ends, but the SWR was pretty good between 1:1 and 1:1.5 (without using the tuner). I took a VNA with me but the battery was flat! Got QSOs in the USA and Russia, so pretty happy. Need to test in better band conditions.
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