QRV on HF from Oxundasjön (Rosersberg) in lunch breaks

Hi Ivan,
It looks as though there are lots of possibilities. With practical problems there always seems to be solutions already published.

I think that ham radio antennas is perhaps one of the most thorough topics of all ham radio projects.
Thank you for the links. I will check these out.

As regards my own box in high winds, I will first try a really simple solution:
Make two holes in either side of the box and push a 1.2m length of 2cmx2cm wood in the holes. That will be small enough to fit in the car, no actual installation effort, other than making the two holes in the first place. The heavy box has already proven to have longitudinal stability, but the two bits of wood will give it latitude stability.

I will probably think about something more "robust" for longer term working. I would like to have a mast to hoist up a dipole, but that is a future job. But for a 60-minute lunch break, the box will be ok.

Just before Christmas I bought a screw-in Christmas-tree foot. It is about 1m long and I was really surprised how stable it is. This is the solution I used in my back garden. A 7.5m mast was stable without any guy ropes, and the inverted V antenna itself adds to the lateral stability.


Very best regards from Harry - SM0VPO

Such drive-on bases can be bought ready-made. They are intended mostly for flagpoles, so search e-shops selling flags and decorations. They are made mostly of steel and cost from USD 30. Here are some types I found in OK:
https://www.vispronet.cz/media/catalog/product/cache/7/image/9df78eab33525d08d6e5fb8d27136e95/s/t/standfuss_4.jpg

https://www.vlajky.eu/vlajky/885/016_Vlajky_eu-teleskopicky-stozar_obrazky-9.jpg?w=830&h=1000

https://www.dobrevlajky.cz/141-thickbox_default/najezdova-patka-15kg.jpg

VBR from Ivan

That is fantastic. I have loads of 1.5m TV mast tubes, 38mm Dia. Using this I could easily have a nice tri-band dipole for portable working with the centre feed at about 9 metres. It would not take more than a few minutes to deploy. That is a great idea 

Thank you for the link. "My cup doth runneth over with glee" 

BR Harry - SM0VPO

Admin wrote:I cannot see the picture, but I get the general idea.

That which you describe sounds simple enough to deploy, and worth some effort and thought  

My only other thought I had was to use a short plank and park the car wheel on it

It is great with these ideas 

if a car is involved, see

http://www.m0pzt.com/copper-pipe-drive-on-base/

I cannot see the picture, but I get the general idea.

That which you describe sounds simple enough to deploy, and worth some effort and thought  

My only other thought I had was to use a short plank and park the car wheel on it

It is great with these ideas 

just to be clear, the above image show the idea, the red triangle is the side support folded up, the blue one is the support folded down to offer better stability

notice that the support don't need to be triangular, a simple foldable leg like the ones used in picnic tables or the like should fit, an idea may be having foldable AND telescopic legs so that they may be extended, this could also allow to use the ends of the legs to tie ropes which can be used to keep the antenna from swinging too much

as for the ropes, an idea may be sliding a teflon ring or a piece of pvc pipe over the antenna whip at (say) 1/2 from total length and using such a support to tie 3 ropes, the lower ends of the ropes may then be  kept down using (say) some bags filled with the snow

to keep the ropes in tension, they may be tied to the bags (or whatever support) using elastic bands

Hi Andrew,
That sounds like a good idea.
I have thought about making a simple tripod with three legs that can fold up. I have already 3D printed two centre-supports and only need to add the legs. The centre-supports work something like an upside down umbrella, but with a big enough diameter that the legs fold up around the coil.

One small thought regarding your "legs" idea, I don't need much to improve the sideways stability due to the weight of the box, so perhaps those metal, spring-loaded, door-legs you see to hold open school doors would be a quick'n dirty solution?

This is a low priority project because the present box protects my radio when it is in the car, but I intended to have a couple of house bricks in the back of the car. Putting those inside the box should make it rock-steady. The box, by the way, is quite heavy, around 10kg. I now have to have it vertical, on it's side, because of the loading coil. That is the only reason it fell over in high winds.

When my antenna fell over, yesterday, I only oriented the box to the wind was blowing to the front, and that did the trick. The antenna, however, was bending alarmingly with the wind, so it was quite a strong wind. I have been using this box method for a couple of years and this is the first time it has fallen over.

Perhaps a better approach could be to make two holes, one at each side of the box and simply push 1" square wooden poles into the 2 holes? That would also have the same effect.

I was on the band today at 09:40 GMT but with 7°C and rain it was not pleasant and the band was a "flat as a pancake". I went down to 7MHz for the last part of the hour. There was a little more activity, but only the "big boys" with their 1000Watts and tri-band yagis, mainly speaking Spanish. 10MHz was ok, but most of the traffic was a bit fast for me. I am a bit rusty and not comfortable with anything faster than about 20 w.p.m. That is why I tend to stick to SSB.

Thank you for the suggestion, I will have a think about it.

Best regards from Harry - SM0VPO (with an empty logbook)

Harry, just an idea off the top of my head; did you consider the idea of adding a pair of foldable "legs" to the sides of the box ? The idea is that by unfolding them they'll lay horizontally on the ground at the sides of the box, so offering better stability, then when carrying the assembly, the legs may just be folder "upwards"

Hi all,
Just a little update, I have got all my stuff together, 36 A/H batteries charged, and having a cart-load of fun in my lunch breaks.

Yesterday I got into Italy (as always) and had a nice 25 minute "rag-chew" with a UK station (Mike).
Today I got (yet another) Italian station, Greece, Germany, and a 59+20 contact with a Russian station - all on 14.3MHz.

 

Today is was rather windy and the antenna fell over (Ivan you were right ), No problem, just turn it round so the wind blows to the front of the box and it is really stable. I could still see the telescopic whip bending in the wind.

I will be on 14.290 MHz as often as I can in my lunch breaks, from 11:30 to 12:30 Swedish time (9:30 to 10:30 GMT), Mondays to Thursdays. If anyone wants to call in you are more than welcome. It will be nice to have a conversation, as opposed to just the "rubber-stamp" QSOs. If it is raining like yesterday then I may give it a miss, or get a nice polythene bag for the wooden box.

The Italian station I spoke to today was a great guy from Varese, 84 years old, also running just 100W into a ground-plane antenna, but his antenna was 29m above the ground. I wonder if there are more retired operators on during the week than weekends? Perhaps Covid-19 has something to do with the weekday HF activity?

So my little portable station is working a treat. It is really great overlooking the lake. No QRM, in fact the bands sound like VHF with the S-meter firmly clamped at 0 on all bands, including 3.5MHz.

Perhaps I can login to QRZ.com from the car, although it could be a bit more time-consuming preparation work in a short lunch-break.

If the weather gets better over the weekends, then I may try to convince Maj-Lis to have a picnic out in the country, beside lake Oxundasjön   Perhaps she will not "fall for it".

Very best regards from Harry - SM0VPO