Sorry but the weather forecast is grim …. I will be there one Wednesday but I don’t like horizontal sleet….
(Mad but not that mad?). Paul
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The accepted theory works fine when applied to the correct environment. Ground like volcanic rocks etc. (such as in Lanazrote, Madeira etc. ) is effectively not there for RF, so on those summits your antenna seems to be hundreds of metres up in the air. So the affect of having low mounted antennas depends on the ground resulting in the ‘wrong’ setup actually working for various definitions of working.
There aren’t any Topband DXers using low dipoles but that doesn’t mean those antennas don’t lead to you having QSOs. Just unlikely you’ll be working the DXpedition 4W8X in Timor Leste 
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… and I was thinking the model works well in a carefully measured environment, but it sits alongside frictionless surfaces and ideal gases which don’t apply perfectly in the real world, much to the disappointment of Physicists. ( Who I was once told were engineers that couldn’t face reality…). Anyway I’ll have to put my compromise antenna to the test, just not in driving sleet, which I suspect would probably render a fail due to it disintegrating…
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Indeed Paul. I have a an 80m full sized dipole I’ve deployed a few times for SOTA. What surprised me was that it worked quite well when supported on a 5m pole. But I’ve only used it on a few summits and each of them had barely enough topsoil to support a tent peg. So it was close to the ground physically but the ground type meant it was much higher in practice. If I took it to some of the fields near here and tried it I reckon it would be pants.
It’s always the case in modelling (I’ve been doing it for pre-silicon semiconductors for nearly 20years) that when the modelling doesn’t fit the theory, you need to find which bit of the assumptions made are not valid and refine those assumptions/model parameters. And repeat. And repeat.
So of course a low Topband dipole will work and let you have QSOs but if they really worked then medium wave broadcasters would have used them instead of spending all the money they did on big masts/towers and finding the right kind of ground with the right conductivity etc. So there’s going to be some kind of antenna that works just as well or better than a low dipole that isn’t so far between the ends that you need to stop and take a break when walking from one end to the other or needs a massive investment in radials or a 40m vertical support!
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Hi Paul @G4IPB, I’ve packed my winter rucksack for the first time this season 
Icom 705, 7m pole, 80m of wire configured as a dipole for 160m, 13.8v battery and the guying system. I’m looking forward to meeting both friends in GW/SW to try some top band fun this evening! It will be great to work you as a S2S if you manage to get out - we will listen out for you! Have a safe ascent and take care! 73
Thanks for the information Stuart - I may have a go from the home QTH, will see. 73
I remember you saying on a previous top band thread we had - looking forward to your results Rob @DM1CM when the spider beam pole arrives and also a S2S would be fantastic one evening! 73
Be good to make a qso with all
73, Ben
GW4BML
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And of course these alternatives do exist and have been used. For instance an end-fed wire antenna lofted by a balloon or a kite. Then there is the possibility of a helical wound vertical fed against a fortuitiously available wire fence. If you are thinking in terms of DX then thoughts of the better antenna will always keep surfacing in your mind, but in this case the challenge is to make four contacts on a band that is often quite well occupied after dark, and the simple low-slung antennas used for SOTA should be capable in normal conditions of working into the near continent, even on phone. Remember the power limit over most of the band is low, 32 watts PEP above 1850, so the UK stations you hear should not be using kilowatt linears!
I must caution against generalisations about rock and soil resistivity. Rock resistivity varies over a range of some four orders of magnitude, not only that but it varies according with the amount of water in it. Add to this that water will seep into joints in the rock and dissolve out minerals, becoming quite conductive. If we take Andy’s example of volcanic rocks, many of those Lanzarote summits are old spatter cones full of cavities and after rain will be much more conductive than after a few weeks of drought. Hard rocks such as the andesite and schists encountered in Scotland will be very low in conductivity, of the order of 10,000 ohm metres, but the water in the rock joints can be as conductive as sea water at less than one ohm metre. To add to the uncertainty a layer of peat can develop a pH of 2 and be very low in resistivity. In practice you won’t know what you are going to get until you try it!
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Damn! - no point in bothering then. Best open another bottle of Aldi “Mouldy Sporran” … errrmm … “Scotch” and wait for oblivion.
I’ll most likely choose Rentschen DL/AM-176 which is nice and flat, good 360° lookout and it’s basically a drive-on summit. It has fairly rich soil, probably at least 20cm deep - it’s the best choice for many miles around. A snapshot from August this year, with a slightly smaller antenna 
:
I may well be joined in the activation by Ed DD5LP if he can kick his thus-far persistent cold … fingers crossed! The plan would be to set up and test in the late afternoon / early evening, head down to a local hostelry to get warm and have refreshments, and then head back up for a 10pm CET start - 21:00z start.
Cheers, Rob
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Some interesting observations have been made about antennas. At this time of year the ground, and I suspect the RF ground, is normally just below knee level in Wales. We will do what we can with what we have.
The antenna is important, but is just one part of a successful activation. Unfortunately I was late getting to the bakery this morning and there were only 2 cream slices left, so I have had to substitute an enormous custard slice for the 3rd portion. The antenna will not be the only compromise.
Ben and I have spent some time in reflection after last year’s cream slice activation and I will be packing some paper napkins.
We hope to speak to you this evening.
73, Kevin
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You REALLY should pack a few of those cream buns as well - purely as an emergency reserve, understand. 
Mind you, biting into one of those with anybody in the near vicinity would result in some serious cream “fallout” … puts me in mind of The Perishers and their “inch-thick ketchup sandwiches”:
Gotta love 'em!
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Exactly Brian. When observation varies a lot from theoretical expectation you must check you are using the right theory. Or measuring correctly. Or both.
OT: I note you will have been licensed for 60 years next year. I think we should have a “Challenge-60 award for being chase by G8ADD” to celebrate this milestone!
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I don’t have a top band set up Ben, will keep an eye on the spots for other bands though. Have a great time you three.
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Well, I’ll have been licensed 50 years next year, so we just need 40, 30, 20 and 10-year licence anniversary chasers and we could have a very interesting “scaled” award.
73 Ed.
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I’ve managed to rig something up which tunes to 160m. It’s just an end-fed wire, as long as I can put in my little garden attached to the IC-705 and AH-705. This wouldn’t tune but I made a 49:1 unun and have added this between the ATU and antenna plus two longish counterpoises. SWR is just under 2:1. It’s compact enough to use on a summit but I will see how it performs tonight. Performance on 80m seems quite good too but with no spotters today on RBN for 160m it remains unproven how much of my 10W is actually doing anything useful.
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Its just a crafty plan to oblige me to chase until I drop, thus getting rid of me!
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Brian is rare in my log book but I’d give it a go. I suppose my MKARS80 might work.
I’m only a youngling, 26 years of ham radio fir me.
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The best SOTA frequencies!
I will call you several times, but do I have any chance to copy ?
Have in mind my call sign, maybe can be heart!
Best success!
73, SV2OXS, Christos.
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Try it out tonight - we will listen for you
Hi Christos,
Keep calling us as much as you can, we will listen out for you would be great to make the QSO!
73, Ben
GW4BML
That was exciting, though ultimately a little disappointing. I think I managed a QSO on 160m CW with Colin @M1BUU/P a little earlier in the evening on G/LD-052, which will be a complete for me if confirmed.
When Kevin @MW0KXN/P posted I could just about hear him and at times, briefly, quite clearly but then he would fade away. But the background noise was strong and I’ve just gone QRT with K at 4 and for me with my wet string hung in the trees the band has closed.
The good news is given better conditions my rig should work, both from the shack and from a summit.
Many thanks for giving me the opportunity to try top band at night and of course the spur to put something together to do it.
Have a safe descent from the summit.
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