Many thanks Rod sorry to hear about the boiler… Sounds like you’re well prepared anyway! Will be looking for you 
73 de Paul G4MD (or G6GGP for this expedition!)
My alerts finally up! (Only a day behind Gerald…) We’ll try to keep as closely as we can to the times but it’s a pretty hectic day to fit the five summits in… We’ve allowed 30 mins operating time per summit, hopefully this will give a reasonable balance between experimentation and getting round them all. Hoping we’ll get to WB-004 just in time to set up in the light…
Hope to catch some of you tomorrow,
73 de Paul G6GGP
I hope to work you, but 2m and 70cm were unuseable today due to a powerful pulsing noise. I have found which house it is coming from and will approach them tomorrow - wish me luck!
There’s an unmentioned issue also to be mindful of, and that is polarisation twisting. Every reflection causes some distortion of the wavefront. I hypothesise that there is greater twisting of vertically polarised signals than of horizontally polarised signals. I suggest this may be why horizontal polarisation works better for marginal horizon-skimming contacts. So in fact the station with “only” a vertical antenna should not give up on signals known to be horizontally polarised such as big gun tropo dxers out at 300-500 km. The vertically polarised signal from the portable half wave or multiple half wave vertical will not end up being purely vertically polarised after a few close encounters with hilltops, trees, buildings, radio masts etc. Similarly the horizontally polarised signal from the bay of 4 x 12 el yagis that the dxer proudly uses does not remain horizontally polarised. Some of the QSB on long paths is due to polarisation twists. We know this because experiments with circular polarisation reveal much reduced fading on incoming signals. Circularly polarised antennas receive equally well any polarisation from zero to 180 degrees offset from nominal. (Some may say, equally poorly, but then, why would commercial fm broadcasters use circular polarisation? The 3db nominal loss is far outweighed by the reduction in polarisation twist fading. )
What this means, in summary, is that the hypothetically pure conditions between two antennas on a testing range, line of sight, with lab equipment connected to measure every molecule movement, are not the same we use in the field, where we learn to ride the waves of QSB, waiting for the signal that went down to come back up again. The VHF dxer knows this phenomenon well.
Even in towns, signals that are regarded as vertically polarised do not stay that way. In the 80s and 90s I used to enter local DF competitions (“fox hunts”) on 2m, which used fm signals, transmitted using nominally vertical polarisation, but I was always using a horizontally polarised beam. I almost always was first or second on the site of the “fox”. I never observed the theoretical 40 db of polarisation loss. It’s just not there in practice.
I read a nice analogy by someone comparing polarisation loss and the precision required to achieve it, with the precision required in a balance modulator. With only a few things not perfectly balanced, the carrier suppression was degraded to 20 db or less. If you’ve built a tube based balanced modulator you know this to be true. (Same applies to “balanced” feed lines).
How likely is it that an antenna with a semi horizontal and imperfectly isolated feedline, not perfectly vertical or stable due to wind gusts and surrounded by reflective and refractive trees and buildings and towers would be able to maintain perfectly vertical polarisation? Not very… so there is really no such thing as “vertical” polarisation from an amateur portable antenna, ie. the ones we use on summits.
Phew, apologies for the long post. This thread is too tempting to ignore…
73 Andrew VK1DA/VK2UH
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Good luck with sorting your interference Brian you have my heartfelt sympathy! Hope to work you. Several times
This is not to say that circular polarisation is without its own problems. The theoretical loss between left hand and right hand circular polarisation is similar to that between vertical and horizontal polarisation, so transmitter and receiver must agree, and an oblique reflection can reverse circular polarisation. Rotation of linear polarization is dependent on reflections and exactly what happens is dependent on the geometry of the reflections as well as their strength.
One of the advantages of horizontal polarisation is that it can follow non-line of sight paths through diffraction. One of the disadvantages of vertical polarisation is that on passing through trees it is more strongly attenuated than horizontal…dependent on the type of tree, of course!
It is all in all a very complex subject, and Andrew is right to advocate caution in applying theory to the real world. As hams our policy has always been to “suck it and see”!
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My J-pole pole is normally propped up against some rocks or other handy object at the summit. So this means, on hearing a weak 2m-SSB signal, I should try leaning the pole over a bit in different directions to see if the signal strength improves.
This effect in well demonstrated by this YouTube video microwave polarization demo (which I used to do as a A-level Physics teacher). Skip forward to the 6-mins mark …
[Sorry about the big image - normally there’s an option to reduce its size or show just the link]
I guess you would need a neat line of evenly-spaced wet pine trees to be anywhere as bad as the metal polarizer used in the demo.
The main problem with trees I’ve encountered at SOTA summits (e.g. Grange Fell GM/SS-249, Claife Heights G/LD-053, Wendover Woods G/CE-005 [the clue is in the name]), is being surrounded by densely-packed wet trees where you get big attenuation regardless of polarization, especially on the microwave bands.
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Brilliant job done today Paul & Gerald on the Favourite Five (No idea about how Gerald went on with 70cms no gear or aerial above 2m).
However Paul - you did a fantastic job and obviously finished Titterstone Clee Hill in the dark. 100% success for me - worked you on all five summits, furthest distance between us 239 Km to Titterstone, nearest distance summit Brown Clee Hill 231 km. Heard G0RQL at R5 on all 5 summits, distance 503 Km.
At this end 100 watts from IC-7400 to Wimo 7 element cross yagi, fixed to pole on house, horiontal polarisation.
73 Phil
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Worked Gerald on Long Mynd from Titterstone Clee Hill today around 13:00 UTC, I was using a 70cms Moxon horizontally polarised, no dip in signal if he was using a vertical… Not worked out the distance as the drive back home has worn me out.
If it works it works!
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Yes, I do this with my J Pole and it makes a difference, espacially with AE contacts.
Compton
Many thanks for the 70cm SSB S2S yesterday Dom. I was afraid that I had missed you when I didn’t hear you when I was on Stiperstones, but we made it when I was on The Long Mynd on account of you being delayed. I was running the 817 barefoot to the 6 element DL6WU yagi at 2m on the Mynd to keep as low a profile as possible. Thankfully there were no wardens in evidence.
Having the 6 element slant polarised was interesting. It didn’t seem to affect the results with those horizontally polarised using yagis and worked well with those with vertical colinears. One unusual effect was that I was found to be stronger on vertical polarisation when beaming away from a station. Obviously the side lobes are somewhat strange with the antenna at 45 degrees. However, when beaming directly there was a good correlation between the horizontal and vertical elements. I was most impressed by the fact that Don G0RQL worked me on all 5 summits and for expediency I only ran the 817 barefoot on two of the summits. The downside to all this was that my design orientated mind was severely affected by the ugliness of the appearance of the antenna at 45 degrees! 
I will prepare a write up of the day in more detail, but would like to thank all that came on to work both Paul and myself. Indeed Don G0RQL and Adrian G4AZS worked me on all 5 summits… and Rod M0JLA would have done, but for some reason we didn’t make contact when I was on Corndon Hill. More accolades to follow in the write up.
73, Gerald G8CXK / G4OIG
An update: the offending unit turned out to be a Samsung branded fast charger. When powered up but not doing any work it generated a wide band chuffing noise that could be picked up on a quarter wave whip on 2 metres and 70cm at a distance of a hundred metres! In future it will only be turned on when needed. I would offer to replace it out of my own pocket but I suspect that as a branded item any replacement would be just as bad!
Pleased to hear that you got this sorted Brian… or maybe not. It would have been good to have been able to work you on 70cm yesterday. I assume that you have shown them where the off switch is for the charger. All you need now is for their brains to be engaged. 
If anyone is wondering is how I mounted the 6 element at 45 degrees, well here is the mount taken from the PIR part of a defunct security light. It was one of those “what are you keeping that for?” items scorned by the XYL. The diameter just happened to be such that with a bit of filing it fitted directly into the top of my pole when reduced to 4 sections. Simplicity indeed.
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Neat!
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Thanks Phil, we had a truly brilliant day out largely due to the band of extraordinarily keen and dedicated chasers who followed us, working us on most if not all the day’s summits. This camaraderie is one of the true joys of SOTA 
73 de Paul G6GGP/G4MD
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Brian - I trust you let them know that it would have been wasting a lot of electricity in generating the chuffing noise…turning up the audio gain would have emphasised the point 
It was good to work Gerald and Paul from all five summits during the day, a first for me, I think!
The slant polarisation worked well from my perspective, Gerald, good signals from all the hills using my vertical white stick colinear.
Interesting that I could hear you working Dom @2E0KIO S2S, but I could hear nothing at all from him -he was using a horizontal Moxon on Titterstone Clee hill, and of course I worked you easily when you arrived there.
I barely heard any of your other callers either, it would be interesting to know if any of them were using a vertical antenna?
On 2m, I think Paul was using a horizontal antenna, and although we worked from all five summits, a couple of the reports were Q4 both ways, and I think it would have been difficult to extend the range much further. On the other hand, I could just copy Allan @GW4VPX on occasions. The path between us is much longer and indirect over the hills, so I guess there is opportunity for the polarisation to change en-route.
If all activators adopted slant polarisation, and chose, say, to have the right hand side pointing down when viewed from behind, attempting an S2S whilst beaming at each other would result in maximum cross polarisation loss. Maybe choose the direction of slope at random, then there is a 50 50 chance of a good / bad S2S!
I can’t think of any other negative, apart from the aesthetics as mentioned by Gerald - and that is offset somewhat by the cunning recycling of a lantern bracket 
Thanks and 73
Adrian G4AZS
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As far as I know it was as follows:
Horizontal - G6GVI, G0RQL, M6KIO/P, G8AKE, G4IOQ (Gez M0NTC used his 2m horizontal beam)
Vertical - G4AZS, G4BLH/M, M0WYP, G4HQB (Phil G6GIY worked on FM from Corndon)
Both - M0JLA, G0NES
This might imply roughly a 50/50 split, but of course it is a small sample.
I think it was a worthwhile experiment and the mounting will be staying on my 70cm antenna for the forseeable future. The arrangement is far simpler than having to swap over a U bolt - you can see the holes for this in the boom. I am thinking of a suitable arrangement for the 2m beam, so there will be even more visual discord on the summits in due course. 
73, Gerald G8CXK / G4OIG
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To clarify - Horizontal 2m/70cm Yagi - 13 element total
but Vertical collinear - receive only.
Thanks to you both for all the summits - busiest day chasing for months.
73,
Rod
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I’ll be interested in pursuing this further, I didn’t have 2 Meter capability with me as I wanted to test out the Moxon (Although I risked high SWR for a 2m HEMA contact). Im expecting a 2 Meter vertical soon so might be fun trying SSB with it. At some point I’ll make a Moxon for 2 Meters.
It was a good day out and the first SOTA this year. More to come I hope!
Adrian, you probably didnt hear me as I had taken down the Moxon and was having a break, only to be messaged the frequency that Gerald was on, so I was holding the Moxon in one hand a few inches off the ground and the mic in another…
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Just a heads-up to the VHF ssb aficionados, and anyone else who wants to give it a go - I’ll be on G/WB-009 as G6GGP/P tomorrow Wednesday 12th Feb. about 11:00, doing 2m ssb (and 70cm if any demand). Only 5W to the SB3 but hope to work a few
For a bit of fun, doing an eco-friendly activation - travelling from home to Great Malvern by train and walking up from there.
73 de Paul G4MD/G6GGP
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