Saturday 26 December 2015

Christmas, and Sporadic What?

Best wishes for Christmas to all my readers.

I have been thinking along three themes over the past few days.

Theme 1 - Why short distance, regular, meteor scatter contacts?

I was just pondering on whether I could actually work SM5EPO under more or less any conditions via meteor scatter (as I mentioned in recent posts). PeO is in JO46 square, 651 km from me, and I had worked him 3 times on 6 metres over a week - though once was on Es after an aurora.

This curiosity stems from my ability to work Henning, OX1JXY in JO46 square (735km) on 4 metres meteor scatter, on a very regular basis, sometimes daily.

Many reference books are pretty useless on propagation, particularly the RSGB Radio Communication Handbook. Once again a book influenced by the "HF dx-nutters" who seem to control that organisation. The ARRL Handbook is a bit better saying of meteor scatter "contacts between 800 and 2300km can be made at 28 through to 432 MHz via reflections from the ionised trails left by meteors as they travel through the atmosphere". I have corrected the text to remove the American spelling and grammar, and they deserve praise for actually dealing with the subject.

From reading things like this I seem to have formed a view that meteor scatter is not very effective over ranges less than about 800km. This will of course depend on the "elevation" of the meteor shower relative to my observation position and that of the other station, plus a lot of other complex influences. However, I tend to use random meteors rather than specific showers, so the elevation I use is pretty variable. So less than 800km seems fairly possible, fairly regularly.

I have read of large commercial projects which used meteor scatter, usually for military purposes. There were all long-distance, e.g. trans polar, and I was not really expecting to have quite so many short distance random MS contacts.

Recently I had a 4m MS contact with OK2BRD on 22 December (JN99 1528km), though it took a hour and eleven minutes to complete the exchange of 5 pieces of information. That is the sort of QSO I had been led to believe would be my lot on meteor scatter. Once again working OZ1JXY on 24 December makes me wonder.

Theme 2 - Es in December

I had a few minutes to spare this morning for meteor scatter, or so I thought. I heard some JT6M on 6m. Quickly turning the beam I worked SM5EPO again. This time though it was not at all like a meteor scatter contact. PeO was putting in a colossal signal. People talk about Winter Es as a pretty thin opening, but this was really powerful.

This screen shot is not the clearest, but it shows me with both 10m WSPR and 6m WSJT JT6M running, as I do when I am watching for Es propagation. I have blanked out the 4m side of the screen for clarity (!).

At the same time as receiving 10m Es from the South, I was receiving 6m Es from the North East. This is unusual for winter Es openings, which are supposed to be very selective.

I was expecting meteor scatter and what I got was Es.

Sadly after that I only had a few more minutes before I was called away from the radio. EI stations were working into Nordic countries for hours.

Theme 3 - Winter Es and solar activity.

I happened to mention to Tim, G4VXE, that I see an association between Es and solar activity, especially when the solar activity is raised but less than what would trigger an aurora, or still raised after an aurora. Tim printed my comments in his column in Practical Wireless magazine with a rather shocked suggestion that it might be a way to predict Es. Well, it makes more sense here than believing the Weather Man's waffle about Es being a wind driven phenomenon.

What did I see today on Solar Ham?

X-Rays elevated, but not enough geomagnetic disturbance for an aurora (though later in the day it got almost active enough for an aurora).

Theme 1, 2, and 3 --- Bringing all this together ---- a comment from Gianfranco IU1DZZ.

Just at the right time, I received an e-mail from Gianfranco, IU1DZZ. He pointed out that "Sporadic E" is just a conventional name. Es occurs regularly, but often for short periods and it is not always useful to us. Great point.

I think that I have been applying myself to the wrong task. My task is not looking for summer Es which we can often use. It is finding winter Es which is frequently hidden and not always of a lot of use. Especially, it is not much use to the many who have turned their rig off for the Winter.

Moving on with this idea, I see that Sporadic E is not really sporadic unless it is viewed from an HF DX viewpoint. OK it is not yet predictable, but it is frequent, maybe even regular, in the sense that it is moderated by certain things (and maybe Solar X-ray emissions).

And moving further away from the original thought, is meteor scatter also more dependable and less random than we thought, as we have been looking on it as a DX tool and not as a short range mode?

Conclusion.

I don't know.

But I will be thinking about it.

73

Jim
GM4FVM

Monday 21 December 2015

First aurora, then the Auroral Es. A good VHF day

In a posting yesterday I said that there were signs of an aurora coming which I doubted might come, but I would be listening anyway.

The aurora had been suggested by the SolarHam site and was predicted to arrive the day before it did. However, I was ready and still waiting for it.

As per usual, the hour or so before it appeared I could hear the OY6BEC beacon on the Faroes and the Carrickfergus beacon in Northern Ireland on 4m. Also present was the GM8RBR 4m beacon on Skye and the GB3NGI beacon on 2m. These beacons had "gone auroral", in other words I needed to beam North-ish, and they had lost their tone. This indicated scattering from the curtain of charged particles streaming down the Earth's magnetic poles and heading for the Arctic Circle (-ish).

The magnetometers I watch had shown sudden signs of life from the days before - this was the start of the wobble which kicked off the "Scottish Aurora" earlier in the week:-



By the day in question (19 December) I was ready and waiting with the rigs poised on the right frequencies. I knew the beacons were blasting away, but you cannot replace hours of good listening.

Suddenly, on the 2m calling frequency was a seriously distorted signal which I could just work out was GM4JJJ in IO86 working a station in Shetland. Then the 4m rig sprang into life on 70.200 with a garbled version of a CQ call. This turned out to be OZ5AGJ, 678km away on JO47 square. New square on 4m! As usual towards the start of an auroral radio opening there was heavy distortion caused by the "Doppler" shift applied by the charged particles swirling their way down the lines of magnetic force.

I tested things out on 2m and worked GS8ASD, but apart from that, all my auroral work that day was done on the 4 metre band (70 MHz). Next I worked G4ODA (IO92 367km), and after that it was a long slog working through a pile up. GM4JR, OZ1BNN, OZ1W, G4BZM, GM4PMK, G0BPU, GU8FBO, EI4EY, GW0GEI, G4IOQ, G3NPI, G3LVP, G4VCJ, G3SHK, GM4DIJ and GM3WIL. Hard to set all that out, so I have made another of my trial maps:-

No lines this time. Not sure how clear this is without them - I am still fiddling around with this. As usual click to enlarge, but you may find it a bit "blocky" if you do.

Anyway, You can see that the 3 stations in Denmark worked early on appear to be the only "DX". Not true, each of the contacts that day was in a different square (apart form GM4JR and GM4DIJ) and several were memorable for other reasons. GM4PMK was a real surprise. He is on the Isle of Mull, and seems to share my interest in things ionospheric. He has his own magnetometers! Anyway, IO66 was a new square. Also, GU8FBO was blasting in here, not only is IN89 a new square, but Guernsey is a new country for me on 4m. With G3SHK being in a new square too (IO90 - how have I missed that!), this was a very worthwhile exercise.

However, I have to say that after days of listening and waiting, plus two and a half hours of operating, I was exhausted. I could never be a contest operator. I like my DX at the end of a long hunt. I could never handle pile-ups like that for hours and hours.

Anyway, on 4m I have now reached 33 countries and 166 squares. It took me 33 years on 4m to work outside my own DXCC. Then a contact in 2010 with Ivan S51DI gave me Slovenia on 4m FM, and since then I have powered away. Joy of joys, I did not even need to try, they came to me, on FM, on meteor scatter, aurora, even occasionally even on CW. Only in a pile up does it become a burden. No need for high power, no need for big antennas. What a marvellous band.

Grand so. But my work was not over. I know very well that after an aurora there can be very nice Sporadic E, often called Auroral Es, but I use that term with some doubts. Anyway, on 10 metres WSPR I was noting OH1KK, OH5XO and SI9AM, from about 16:10 onwards. The aurora lasted here from 15:20 to 17:50. I kept an eye on the 10m Es, and they were still going at 21:00. That is a classical Auroral Es path so I thought that I should give VHF a try later.

It helped that Mrs FVM needed to watch something on the television. Some show were they line up daft dreamers, turn them into supercharged bullies, and then select the worst personality and give them a highly paid job for a year. It seems to be run by a quarrelsome barrow boy who runs around in a Bentley and wakes these duffers up at odd hours of the morning. Then they make eedjits of themselves running stalls selling some dire product, trying to outperform the others. I cannot see the point of it. So as it was the final I had two hours to spend too, which I used listening hopefully while doing my QSL cards.

At 21:53, right on queue on the 4m SSB calling channel came OH1AXT (KP10TJ 1582km). Great QSO, and he was a clear as a bell and a huge signal. No need to struggle with the distortion using Es, unlike aurora. I could not raise anyone else on 4m, but 6m was humming, and I went there and worked SM5EPO - again. I had worked PeO twice last week during the Perseids meteor shower. Good to hear his voice. Then OH1LDI and OH3VZ, (KP11 and 12, 1589 and 1584km).
Oh, I don't know about these maps. I am not sure if they add much.

Anyway, what a great day. I let the 10m WSPR work on until about midnight, and it had finally faded out at 23.22, but not before the Nordic stations mentioned earlier had been joined by TF3HZ proving the Auroral/Polar connection, but also EA8BVP. Canary Islands are a regular here, even when the band is not good. Is that Es? If so, is it auroral? If not auroral, what is it? Oh yes, and there were even a couple of Stateside WSPR stations too.

The Es session was shorter than the Auroral one, but a lot more pleasure. I enjoy that challenge of aurora, but this one was pretty limited.Of course I am happy to work all over the UK and Ireland, plus Denmark, but some real auroral DX would be nice. How do I manage that? Oh yes, CW. I know I am missing out on a lot of DX because I can hear it on CW but cannot respond. Why not? Erm. Because I am spooked by the high speeds they all do (and don't say they will slow down, because I tried that and they definitely do not slow down). Anyway, Es was a real doddle and with Es you can forget CW, which I do quite happily.

There are a good few people who turn off their radios in December and reckon there is not much on. Once upon a time I would have done the same. Yesterday was a good day to have the radio turned on.

73

Jim
GM4FVM

Sunday 20 December 2015

Geminids meteor shower 2015, and a "Scottish aurora".

The Geminds this year were "scheduled" to start around 7 December, to peak around 14 December and end around 17 December.

I found some enhanced meteor scatter activity between 12 and 15 December. The result was that I worked:-

6 metres:-
OE5MPL (JN78, 1387km), EI4DQ (IO51 369) and SM5EPO (JP80, 760)
4 metres:-
SP9HWY (JO90 1543), OZ1JXY (JO46 735) SP2JYR (JO92 1387) and OZ1JXY (JO46 735)
2 metres:-
OZ3KGJ (JN65 1544), IK5YJY (JN53 1696) and SP2IQW (JO94 1319).

I actually worked SM5EPO twice on successive days, which is interesting in itself. Could I work him almost every day (like OZ1JXY)? I never expected these things to occur on meteor scatter, which I thought produced very random results.

I mentioned all this to Bob, G3KML, who pointed out that 2m was getting me furthest.

Leaving aside working SM5EPO twice, the average distances are
6 metres: 838
4 metres: 1100
2 metres: 1519.

It is a very small sample, but he has a point. This supports my own experience, from which I draw the anecdotal theory that on 6m the reflections are weak and long lasting, on 2m they are strong but very short, and 4m is a mixture of the two. So you can get further on 2m with strong reflections, but the contacts take longer with long gaps between the bursts. On the other hand, 6m allows you to have reasonable contacts with simple equipment a lot of the time.

I have finally bought a licence from EI8IC for his mapping software. The delay was due to a quirk in Windows 10 at my end. I had to sign in on another computer, pay and register, and then register this computer to that subscription. My problem, and $15 isn't much for such a useful tool

I have made a map and added some lines, with 6m Blue, 4m Green and 2m red. Sorry, I forgot to add OZ1JXY, and I hope Henning will forgive me. I had to use several bits of software and it has lost some of its crispness due to compression at various stages. On reflection, adding the callsigns and leaving off the country names might have been better.

Anyway, you can see what Bob means. 2m does seem to get further as you might expect, but not much. But the maps are not based on great circle paths. Although several of the contacts were roughly the same distance, the best DX was actually IK5YJY followed by YL3HA. The maps does not make it look that way, so the projection is not ideal for some purposes. Still I will press on and I might correct for the projection later.

Still, I remain convinced that meteor scatter is an entirely different beast on 2 metres. Most people use JT6M for 6m and FSK441 for the higher bands. That supports the theory that 2m bursts are shorter, as the modes are tailored for those characteristics.

Also, I could hardly work Italy on 4m at present as Italian stations are not licenced for the band just now. I have worked Italy on 4m meteor scatter in the past, but it was hard work. Nor is 4m available in Sweden, nor 6m in Russia. So the pattern I find may be skewed by these issues.

There is another underlying factor. Perhaps I do not work as far on 6m as my heart isn't in that band. 100W and two elements (even though they are phased elements) does not look like a lot of commitment. On the other hand, on 2m I have 200W and 7 elements. Or maybe it is the reverse, perhaps I NEED a better station on 2m due to the characteristics of that band.

Either way, my station is modest by meteor scatter standards. Most meteor scattter stations have huge linears and vast towers. My station is modest on all bands by that standard. But I still get results.

Moving on, there was a "Scottish" radio aurora on 14 December. Amateurs in The Beautiful South tend to call any aurora which does not reach them "Scottish". In other words, hardly an aurora at all. Here I heard the Faroes beacon on 70.035MHz (OY6BEC, IP62, 735km) with auroral tone. A Scottish aurora might be small beer to those in the "Home Counties", but up here 735km is a fair old haul. Hey, down there they get Trans Equatorial propagation, which we do not get in the frozen North.

Also heard aurorally during the 14 December event were the Carrickfergus and Buxton beacons on 4m, and the GB3NGI beacon near Ballycastle on 2m. Then I worked Clive, GM4VVX on aurora on SSB. OK, a "Scottish" aurora, but good fun all the same.

As I write (20 Dec), the follow up shower to the Geminids, the weaker Ursids shower, is with us. I am hearing various reflections on 6m. Also, we have an ionospheric disturbance from a pair of coronal mass ejections. These two outpourings form the Sun are not having much effect here so far (it is the middle of the day and I usually expect things to liven up, if at all, after 15:00).

Will things liven up? Probably not.

But I will listen anyway.

Jim
GM4FVM

Tuesday 24 November 2015

UK Amateur Radio licensing - what's wrong?


I have been a trainer and assessor under the UK licensing system for some years, and a holder of a licence for 40 years or so. It is difficult for me to understand what it must be like to be a new entrant to our hobby.

I have had discussions with many people about this, from those wishing to become licensed to those who have held licences for longer than me. There are a lot of opinions about what is wrong with it, and almost no common aspects to all the views about what to do.

From what I can see, decisions tend to be taken about these things during panics or when the licensing authorities are putting pressure to sort something or other out. There is not a lot of logical thinking. Instead of planning in advance, things tend to get left until it is too late to sort them out. I think we should have a plan now, discuss it with the authorities and be ready for when we next need to visit this thorny topic.

There are three classes of licence in the UK - Foundation, Intermediate and Full. There are three exams, Foundation, Intermediate and Advanced, and they give you access to the related class of licence. You have to take each one in turn (you cannot skip the lower ones).

I do not really have a problem with the three exam and three stage system - in theory. It is supposed to encourage people to learn about radio as they progress, and some of them do, while some do not progress beyond whatever level they are now. It is hardly surprising that many stop at Foundation level, as they are new entrants and may find amateur radio is not to their liking. But quite a few get to Intermediate and stop there, so they have been in the hobby and taken a second exam, but choose to go no further.

Recently I heard from a former work colleague of mine who has just become a radio amateur with a Foundation licence. I am really impressed with his enthusiasm. He does not have a radio technical background, he has just taken up a new hobby. I knew him 20 years ago as a respected colleague, and I would never have expected him to take up an interest in radio. So, good for him. He tells me that he wants to learn and progress through the exam stages as he learns more about the hobby. I do wish him well and I am very pleased that he has joined us.

So this brings me to wonder just how the current system encourages him. And I reckon it doesn't.

The basic difference between the levels in UK licensing is a series of power restrictions. So a new entrant to the hobby gets almost full access to the amateur spectrum, but is limited to unmodified commercial equipment and 10 watts (PEP at the antenna). Intermediate gives 50 watts and broadly the same bands, but they are also entitled to build and modify their own equipment. Full licence gives 400 watts and a few odd slices of bands, plus the ability to operate abroad under CEPT agreements, maritime mobile, etc.

We can think about the Foundation as being equivalent to a start-up amateur getting at least slightly better terms than someone starting out in CB radio. That was how it was put to me by an RSGB President. He said that Foundation entry was to make amateur radio as accessible as CB. The power level of 10 watts and the requirement for commercial equipment was a trade off to allow the licensing authorities to permit those with just a basic set of skills onto the bands (but from the RSGB's point of view, still be in a better position than going into CB).

I can see that argument. But those going into CB only get very limited VHF and 11 metres. So why do Foundation amateurs get almost every band? That RSGB President replied that to attract new entrants to amateur radio you need "the lure of 20m and worldwide DX".

At this stage it might be worth noting that that particular RSGB President (and this was a few years ago) was a DX-obsessed nutcase, and not all of us a quite so stirred by the idea that 20 metres is the biggest draw for the new entrant to the scene. Just for example, I haven't used 20m much for decades. In fact, I never have. In my day it took me 2 years before I was actually licensed to use it, and yes it was an issue, but not the only one for me. He seemed to be talking about a licensing system to attract people just like himself, whereas I am thinking about a wide range of people, technicians, earth scientists, Moon-bouncers, rag-chewers, data-nuts, UHF gurus, repeater junkies, antenna jugglers ...

Now here is the gaping hole in the system for me. Yes, I agree with him that for many the lure of world wide DX is useful. But do you need to get it all (in frequency terms) at Foundation level? From what I can see of progressive licensing levels in other countries (e.g. USA, Australia), those starting off at a "Foundation" or "Technician" level may get similar (or more!) power, but they are restricted in the bands they can use. Yep, sure the lure of worldwide DX on 20m is there for them, but not until they have progressed a bit further. And I think we should do the same in the UK.

I cannot believe that my friend would not have joined the hobby if he was offered 10 watts, all UHF and VHF bands, 10 metres (so far better than CB), and then maybe WARC bands, 80 metres and/ or Top Band. And with some of those higher bands, maybe I would offer even more power than 10W if the licensing authorities would allow it in certain bands. But the elusive HF "DX" bands would have to wait until they had progressed a bit further, and that would be a big encouragement to progress further.

I could have had a ball on those bands with a Foundation licence, and I would have had far more incentive to progress than the present system provides. Also, I think it would have wide appeal to those others not totally besotted with 20 metres as well as those poor souls who are. Enough to get you hooked, but not so much that you don't progress.

Then for Intermediate I would offer the same bands as Foundation, but add 40m, 15m, and more power (at least 50 watts). And now you would see the lure of worldwide DX becoming a spur to progressing even further. And I might offer Intermediate licences 100W on VHF and UHF, making this more like a technician level and something which is just fine for those who love the higher frequencies (and in doing so, maybe they will stop there if they choose).

Finally for the full licence I would leave things as they are. This would mean that Intermediate licensees would be bringing activity to 15m and 40m while they study for the Advanced exam, and at the same time realising that that lure of worldwide DX and full power is just around the corner. 15m and 40m would be a great apprenticeship for progressing 20m (just as much as 10m and Top Band would have been a great apprenticeship for them earlier in their career).

As to the exams, I would leave them much the same as they are. From my point of view, the leap from Intermediate to Advanced exam looks very daunting for anyone who does not have a background in the electronics industry - like myself and my friend. So I would tweak the exams to be more like the reality of the current situation. It now matters less that someone might not be able to open their rig and fix it, as very few of us do that any more. But there are lots of areas in which amateurs still make advances and are still experimenting --- but these areas are poorly covered in the exam. Areas like antennas and propagation.

Why should it be that an amateur needs to know how to build a rig (which almost nobody does) when they don't need to know about how to build an antenna or understand Sporadic E, which most of them have to deal with in ignorance of the basic principles.

But the major flaw in the current UK rules is a really glaring error in my view. At present the distinction between the grades is set in power terms, which is unenforceable. If you heard a Foundation licensee under my plan on 20m you would know they are cheating, whereas under the present system if you hear a M6 using 400 watts you would be none the wiser. We should not have set up a system which is impossible to enforce.

The Intermediate exam of today still requires candidates to understand a block diagram from a 1960s valve era superhet rig. With SDR rigs becoming more and more common, how can we persist with this? How can we pretend that knowledge of building a rig is necessary when many existing amateurs (including myself) cannot do it? Yet I can do useful research into other aspects of the hobby, and I am not alone.

So my plea for the future is this ... please bring in an enforceable system which offers the big prize at the end of your study rather than the start, and please make it obvious when someone is cheating.

By the way, the CB book in the picture has been loaned to me by Doug, GM6ZFI. It dates from 1977. It probably gives as much information about radio theory as most amateurs need, but rather a lot more about propagation and antennas than they seem to know at present.

73

Jim
GM4FVM

Sunday 1 November 2015

Getting started on VHF DX

This is a basic introduction for those who are interested in what happens at VHF but who have yet to take the plunge.

It assumes that you have already dipped your toe into VHF via some FM operation, and you have a VHF rig or might buy one which has VHF bands.

It used to be so easy. In my day, my licence only allowed me to operate on 144MHz and above, so I had to. And then to begin with, there was only one rig - the "Belcom Liner 2". Before the Liner 2 you could use an HF rig with a transverter, a complex and expensive solution. Then in about 1973 the Liner 2 appeared which offered 2m SSB in a single, dumpy, heavy, awkward box. It also did CW, but the "Class B" licence did not allow me to use CW (and no doubt created my life-long fear of the CW mode).

There was this large pool of enthusiastic Class B licencees, and suddenly there was this rig. So hundreds bought Liner 2s and went up hills. And as the Liner 2 was awful (it has been called the worst rig ever sold) things were a bit fraught, especially when people started trying to increase its 7 watts or feed amplifiers.

After a while the big three manufacturers followed suit. I bought the Kenwood offering - the Trio TR-7010, which had the SSB bits from the (about to be released) TS-700 multi-mode 2m rig. Yaesu had the FT-290 and Icom the IC-202. These rigs were all aimed at different segments, but the one thing they all had in common was that people took them and went up hills, or worked with good antennas from their homes. VHF, or at least 2m, was transformed into a band where you could get good long distance DX contacts almost all the time.

It isn't like that now. There are no "Class B" licences in the UK any more, as they were all converted into Class A. There seems to be a lot less enthusiasm for 2m portable work, and we now have 4m and 6m to compete for our attention. There are no 2m only SSB rigs either.

We now have an exam syllabus that barely mentions VHF, and quite a few pass their exams unaware than VHF is very well suited to DX working. VHF does not mean "FM". OK, there is a lot of FM on VHF, but there is also lots of CW, SSB, data modes and so forth. And VHF is no longer just 2m in Europe, but is now 4m and 6m too.

So this posting is realistic enough to accept that you are not likely to find the same heights of activity as people fondly remember from the last three decades of the last century. But what you will find is a lot more, better equipped, well located stations, usually working from home, and a lot of keen contest operators. And of course some of the most astounding propagation you could imagine. The scene may have changed, but the bands are still as good as ever.

So let us assume that you have a rig which covers VHF. Plenty of folks do. They have a rigs which they use for HF, like the FT-897, the FT857, the IC-7000 or the TS-2000. These are fine equipment for VHF. Having said that, a lot of operators never use them on VHF, but stick to HF. And a few have rigs like the FT-817, often kept as an HF standby, which could well be used for VHF DX.

What would be needed to get this equipment going on VHF so that some DX could be worked? Not much actually. If you want to try 6m (50MHz), you may already have an HF antenna which would do some service. I have a G4MH mini-beam. OK, it does not work very well on 6m, but well enough to bring me summer Sporadic E (don't worry about the propagation modes, more of that in a later posting). Summer is a great time for VHF DX, but there is always something happening.

If you already have a "white stick" vertically polarised VHF antenna and use FM, you are only seeing a very small part of what 2m can do. VHF DX is mostly sent with horizontal polarisation, and if you are working on the wrong polarisation your losses are huge. Yes, you can listen about on your FT-817 or whatever using a vertical, but you will not get much in the way of results.

So the solutions I am going to suggest are for simple horizontally polarised antennas which will certainly get you going.

Antenna 1 - the 2m band Diamond A144S10R (not to be confused with their 10 ele 70cms antenna!).
This is a compact (2.13m boom) yagi-type beam which offers 11.6 dBi gain (which is about 9dB gain over a dipole). It is light (just over 1Kg) and small enough to look pretty inconspicuous. It looks a bit like a TV antenna and the neighbours will hardly notice. Of course with a directional antenna you will need some sort of a rotator, but this one can be turned by a light duty "TV" rotator. Or you can slip it onto the pole above your HF antenna if that already has a rotator. The only reall snag with this antenna is that the maximum mast diameter is 47mm which is too small for most "2 inch" poles. I just drilled another hole in the boom and fitted a larger mount, or you can use any general "boom to mast" clamp, but be careful not to over-tighten it and squash the boom flat. Presently available, on eBay, this Diamond antenna can be bought for £90.

Antenna 2 - the 6m band Diamond A502HB
Another compact from Diamond, this one offers about 6.3dBi gain (or about 4dB over a dipole). It is small and light with a very short boom (0.75m). This antenna is often described as a yagi, but actually it is more like an HB9CV antenna. It has two driven elements with a phase matching connection running along the boom. Of course it is a lot wider (3m) than the 2m antenna listed above, but it still looks very inconspicuous. It could easily sit above an HF beam and be hardly noticeable. And despite the weather here, I have mounted it above a "TV" rotator. This is an effective 6m antenna and capable of working modes like aurora and meteor scatter. For sale as I write, on eBay, for £93.

The photo above shows a Diamond A502HB on a Conrad TV rotator. The common Hy-Gain TV rotator is similar.

So these two Diamond antennas are recommended by me after having used them for several years. They are NOT the best DX antenna, but they are the sort of thing you can put up to try out VHF and see how you get on. Both would fit above an HF beam, and either could go above a lightweight rotator.

I might add that Comet make an antenna very like the 6m Diamond one, but over the years I have found Diamond construction to be better than Comet (just my personal view). And then others make HB9CVs too, but I have not tried them out.

So we have two antennas which remove the idea that VHF antennas have to be expensive, bulky and difficult to get. Then there is the co-ax. By all means try cheap co-ax, but RG-213 is really the place to start for higher VHF. RG-213 is thicker and more difficult to work with than normal HF co-ax, but it offers many advantages.
On top is RG8 (mini) which I often use for HF. Below is RG-213, which I use for VHF. Obviously the 213 is thicker, but the key advantage is that the losses caused by attenuation at VHF are much lower with 213. At 100MHz, on a run of 100m of co-ax, 213 will have about 10dB less attenuation than normal HF co-ax. Even at my lengths (30 metres or so) at 2m the result of using 213 is to just about double the power reaching the antenna, and also to double the signal on reception. Worth having.

Actually, for 2m I use Ecoflex 10 co-ax for even better results than 213. At 50MHz, where standard HF co-ax could be used, I also use 213, which some would view as a bit over the top. OK, but I am a bit of a VHF enthusiast. For general use, RG-213 would be the standard for 2metres around here, though most people use standard HF co-ax for 6m.

What could you hear with these antennas and this co-ax? Answer: a lot further than you can with FM and a vertical white stick. 150km on 2m should be possible under flat conditions. If there was any tropospheric propagation then up to 1000km should be possible. With sporadic E I have worked as far as Belarus on 2m - though that is reasonably rare on 2m. I have often worked 1500 km on 2m meteor scatter using the Diamond. For 6m, I have worked all over Europe on meteor scatter, and likewise all over Europe on summer Sporadic E. Best dx from here on 6m so far is Puerto Rico. Remember this was worked on a simple Diamond 2 element and 100 watts.

Maybe now I have moved up a step with better 2m antennas and better co-ax. But I still did amazingly well with just the Diamond and RG-213. And for a rig I also have the FT-817, plus a little RM linear which boosts my power by a useful amount. On 6m  I still use the Diamond. Yes, I have made life a lot more complex but it does not need to be. Certainly for starting off, these simple antennas are very effective.

There you are really. Why not try VHF DX? With a rig you probably already have, some co-ax, and a fairly lightweight antenna, you can make a start.

73

Jim
GM4FVM

Monday 26 October 2015

Ham radio is a big enough hobby for everyone ...

I did not start this blog to pour out home-spun philosophy.

(Why did I start this blog ?)

Anyway, here are some more thoughts from my forehead.

I just wrote a very long outpouring justifying every thing I do. The idea was to graciously allow you lot to do what ever you want so long as I can do the same. I've deleted it.

In brief (this is brief?), the idea was:-

I don't do CW (mostly because I don't think I am any good at it, but also I am scared of people who go too fast)
I don't enter contests (mostly because I am uncompetitive)
I don't support my local club (mostly because they don't support me and the work I used to do there)

But because I do not do any specific thing, that does not mean I want it to be stamped out.

You are all welcome to do it. I do not want to convert you to my way of thinking. I just want to explain my motives and my odd ways of doing things. You are free to ignore me, do your own thing, and generally carry on as before. It is a free world and it is up to you (and me) what we do.

I am just glad you read this stuff. Use it or not - it is a free world.

Sometimes I hear from people who maybe get the idea that in this blog I am trying to promote some great plan or something. No, I just want to explain what I am doing. I am not trying to convert you. I just put out my ideas, and you can ignore them all you like.

I think this comes about after a conversation with a great VHF DXer with a superb location and HUGE towers. He said that he would "see me on KST". KST is a VHF-ers chat site. I tried it and found it the most boring place in the world (WORSE than our local club).

So I said "I am not on KST" and he replied in an agitated way "What, you want us to go back to the dark ages without the cluster and no computers or e-mail and all that?".

Erm, no, that is not what I said. I pointed out to him that I am all for things like KST, I just do not do that particular part of the hobby myself. He did not seem very impressed. I told him I get contacts by calling CQ or replying to others. What a shock for him that was.

What I find with KST is that people sit there and watch it as a substitute for listening on the bands or calling CQ. Well, that is up to them, but it is not what I do.

Just because I do not do KST or Echolink, or something else, does not mean I want to go back to using smoke signals or carrier pigeons instead.

There are large parts of this hobby I do not do. You are just as entitled as me to do parts and leave out other parts. You can even leave out the parts I like. Work away. Just because I don't do it does not mean I want it stamped out.

Or you can do any part of it your unique way. I listen on 50.999 for DX, copy the morse, and post the reception reports on the DX Cluster. I don't work them on CW because generally they are sending so fast I have no hope of working them. So I do it at a level I am comfortable with. I like it that way. What's the problem? And you do it your way, and I am keen to hear of your success.

I do not enter contests because I am not competitive. At school I hated competitive games (the games master had a need to line us all up and examine us for "unhealthy" underwear by pulling down everybody's shorts in quick succession, which never helped). I could not see the point of trying to win the sprint race. But when he set us gruelling circuit training of climbing bars, jumping vaulting horses and lifting huge weights, I excelled. Because that was competition against myself and the watch. I was trying to do better every time in an absolute sense, and I loved that.

So I am not competitive, I never have been, but I love setting goals and beating them myself. No contest entries from me, but if I can work somebody further away in a contest and learn something, that is what I do and we both gain.

Please take this blog as a simple (!!!) explanation of what I do,. If any of it is useful, feel free to use it to develop YOUR hobby. But there is no need to do it like me, and I think you are fully entitled to do it whatever way you want to (even if you use KST, enter contests and run sprint races competitively).

That other photo was just the "red" cooking apples, by the way. Here are some of the "green" cooking apples. Some of the red cookers are partly green, and some of the green cookers are partly red. I have to leave it up to Mrs FVM to sort it out. Had a great apple crumble last night though.



73

Jim
GM4FVM

Sunday 25 October 2015

VHF is not "line of sight", or not more than HF already is.


Well, the image is some of the apple harvest Chez FVM, minus the red eating apples off the new tree, and minus the russets. No doubt there will be a few more to pick over the coming days. No pears this year though.

But anyway ...

Yesterday I visited the "Fog on the Tyne" radio rally at Gateshead. That was the first time I have been there. It was smaller than our "local"one at Galashiels but still crowded.

At the rally, I found myself chatting about VHF to Gordon G8PNN and Eddie G0EHV. We agreed how awful it is that VHF is often dismissed as "line of sight" communication. Well, this is also said of UHF, microwaves, and really anything that lazy amateurs do not want to bother with. I can be lazy myself.

Yes, VHF is used for point-to-point line of sight commercial communication. It is also used by amateurs for similar VHF purposes. And a mighty fine line of sight method it provides. It is used for mostly FM mobile chats using vertical antennas and often repeaters. But it does far more than that. And it means far more than that to me.

VHF radio signals are no more "line of sight" than any other radio frequency. Essentially all radio energy is identical to all the rest save for a few factors, and radio is the same as light. So it is hardly surprising that radio signals follow lines of sight, as apart from the frequency radio is light.

So we look along lines of sight and think, "light travels along lines of sight". Obviously this is true as we can see things far away, and if anything gets in the way, we do not see them. But what if the thing that gets in the way is a mirror? Well, although we still think light travels in straight lines, we are happy to look at it after it has been bent back through 180 degrees. Or if we put a pencil into a glass of water we see the light bent by refraction, so we know perfectly well that some things bend light. The light is bent, not the pencil.

And we are happy that some things bend radio. The old HF hacks who dismiss VHF as being "line of sight" know that their HF frequencies are refracted (and partly reflected) in the ionosphere. But they do not seem to realise that the same processes which bend HF signals do exactly the same for VHF signals.

What I am saying here is that all types of electro-magnetic radiation, radio "waves", light, ultra violet and infra red radiation, X-rays, gamma rays, the whole lot, go straight or are bent in exactly the same ways.

We can look up to the sky and see stars which are so far away that the light takes thousands of years to reach us, so we know pretty well that it can travel in a straight line uninterrupted for a long way, so what can bend it?

Light and radio and all the rest of the EM spectrum will travel in a straight line unless affected by:-

Reflection ("bounced back" as in light from a mirror)
Refraction ("bent" as by water in glass or a lens in your glasses)
Scattering (randomly changing direction after hitting something)
Gravity (tiny effect of passing huge objects like stars)
Absorption (entering a dense medium which stops the photon and releases its energy).

We do not see much effect from gravity as we do not usually encounter star-sized objects to do it. But the others we do meet.

VHF radio signals (and the millions of packets of energy in them - photons) can be bent and scattered and reflected just the same way as HF radio signals. It is just that it does not so happen that they get regularly sent back to earth from the ionosphere. Instead they get irregularly sent back to earth by all sorts of things.

It is true that the difference in frequency between HF, VHF, UHF and everything else (e.g. light) means that different results occur, but the processes are still the same. The ionosphere might be more or less transparent to the light frequencies (just was well for the apples ripening), but it might refract some frequencies and not others. However, the basic ideas are common throughout the spectrum.

So VHF amateurs have fancy names to explain their particular means of bending their signals, but the processes are just the same.

Reflection
Sporadic E is largely reflection (or so we think) - from an ionised layer in the ionosphere. It also affects HF, so there can be no argument that it is OK. The reason why this process occurs is not well understood but the result is pretty common. Today (on 6metres SSB in October) I worked EA5/G3XGS in IM98 square in Spain, 1981km away. Line of sight does not carry to Spain. I cannot look out the window and see Spain because of the curvature of the Earth (and absorption and scattering too!). My signal was bent (reflected?) back down to earth by a layer in the "E region".

Radio signals can reflect off objects too (that is how radar works). However, it is a surprisingly inefficient process. As Earth-Moon-Earth operators know to their cost, only about 7% of the energy hitting the moon comes back, and the path losses have to be added to that. Radar generally works with huge power and short paths. Still you can have QSOs using reflections off aircraft and ships.

Refraction
It is not just the HF boys who get to use refraction. Tropospheric refraction brings irregular "lifts" to VHF stations. This process also works very well at UHF too. I can regularly (well, occasionally) get 1000km+ paths on VHF using "tropo". Normally, the air density declines with height, but during tropo this can be reversed. This can bend the radio signals back to earth.

The process of tropo refraction is fundamentally just the same as F-layer refraction. A difference in density of the medium causes a deflection of the radio energy path. OK, ionisation is not present, but then ionisation is not the cause of F-layer HF refraction, it is the necessary pre-condition for it. I know that idea gets a lot of folk jumping up and down, so no doubt we will return to it.

Scattering
VHF types love scattering. For HF people scattering is just a thing that happens, and it allows them to work some extra stations. VHF enthusiasts go out and look for it. Two common methods used are auroral and meteor scattering.

Essentially the process is the same. If light hits a (non-reflecting) surface like a wall, it gets scattered all over the place (just as well or we would walk into the walls). So the same is true for radio. Auroral and meteor scatter happen at about 100km about the Earth thanks to the density of the atmosphere at those levels, which is very handy for us. You can get scattered radio signals from other things too (like rain!), but these two are very handily placed for VHF contacts at 1000 to 2000km .

The radio signals reach the ions spiralling down the magnetic lines towards the North Pole, or reach ion-trail of the meteor as it burns up in the atmosphere, and they try to pass through the denser material. If it was too dense they would be absorbed, but luckily for us, enough get thrown in all directions for a useful proportion to head back to earth. The process is complex - as they hit, say, an electron spinning round an ion they will be thrown out, affecting their energy level and quite possibly causing slight change in frequency and direction (causing Doppler effect distortion). So they might be hard to copy, and the signals will be weak as scatter is not directed but thrown all over the place, but it works.
====================
OK, you get the picture.

VHF is not just "line of sight". VHF signals are reflected, bent and scattered in much the same way as HF. Different frequencies and energy levels make different things happen, but the processes are exactly the same.

There is no mystery about all this. I really believe that the current (UK?) amateur radio training syllabus is too heavily biased (!)  towards electronic theory and covers too little of the physics of radio. This leaves me and others spending years finding out the most basic principles of our hobby, without the help of well written text books. 

Rant over.

73

Jim
GM4FVM

Thursday 22 October 2015

What a great hobby ham radio is.

I know that amateur radio can be technical and social. Certainly it can involve electronics, physics, earth sciences and all sorts of complex science. But it is often promoted in the UK as being a social pastime.

In the UK, our "national society" promotes the social side as participation in local societies and their contesting activities. To me this conjures up the image of old codgers moaning about the biscuits at the meetings, and poor souls up to their oxters in cold mud pounding vainly on morse keys. So the social side, as represented by "the powers that be" does not really appeal to me. You can guess which clubs created those images in my head.

But another aspect of the social side is very important to me. Being "communication" people we can always keep in touch. For example by this podcast and others, by emails, and even by radio. So it is my contacts with individual amateurs over the past few days which have struck me.

Richard, GI4DOH, posted a nice note on my last posting, wishing me good DX with my new antennas. Thanks for that. A bit of encouragement is what we all need sometimes and this was particularly well timed.

And then Andy, GM4JR sent me an email agreeing with my comments about the poor element fixings on the Sandpiper beam - he uses one too. And he suggested what I had been thinking, it might be possible to re-engineer it. My own plan was to replace the element fixings, change the boom mount, and replace the braces. I was great to hear from someone who can confirm and develop these ideas.

Doug, GM6ZFI, contacted me and we agreed to go out for an early lunch (which turned out to be a sausage roll). Doug had asked for the 10 element Diamond. It is a bit bent and there was no cash charge for it, though Doug paid me with:-


a tin of Diet Coke,
a caramel slice, and
half a bag of cable ties.

Very nice. Good to have a chin wag and complain about everything which is wrong about the in the radio (and railway) world. I worked Doug on 2m later after he had put the Diamond up on his mast in 60kph winds.

When I got back, the postman handed me an envelope which contained a book called "The Radio Amateur's Hand Book". I had loaned this book to Bob, G3KML. I might point out that it was written in the 1920s (no date on it), and has been reprinted. I missed the Galashiels rally on Sunday so Bob posted it back because he couldn't hand it over there.

It was a pity that I could not make the Galashiels rally, but I hope to go to the "Fog on the Tyne" rally on Gateshead on Saturday. I might meet some more of these interesting people.

This evening Chris, GM4ZJI, phoned me up to tell me he was on 2m working a German station on meteor scatter. I went straight to the frequency for what was an excellent test of the new Wimo antenna. For over a hour I collected signals from Germany. Thanks Chris, and thanks also for spotting me on the DX cluster.

Now, have I got the social side of this hobby wrong? Can I leave that image of boring meetings behind me? I can see that lots of people are contacting me and we are developing new ideas and plans.

This posting is all about people. The image of amateur radio is not all about Tony Hancock types in isolation. It is about working together and supporting each other, either in person or by "other means".

Thanks folks.

73

Jim
GM4FVM

Wednesday 21 October 2015

Wimo DK7ZB and Vine Eagle antennas.

I have added a Wimo WY-207 7 element 2m yagi and a Vinecom Eagle 4 element 4m yagi.

Down come a Diamond 10 element for a 2m and a Sandpiper 6 element for 4m.

So why do it and what are the new antennas like?

Before

After


Well, for a start the 2m antenna is above the 4m one. Before it was the other way round because of the support struts on the old Sandpiper. Much study of height gain tables led me to agree with almost everybody else that the 2m one should be the higher of the two. So that basically required a non strut type construction for the 4m antenna, and thus a smaller, stiff, boom.

It was always my plan to replace the 10 ele Diamond with something longer. Ideally that was going to be a 9 element Tonna, but Tonna are in the middle of one of their non-manufacturing phases, so I could not get one. The Wimo is slightly shorter at 3m boom and otherwise seems comparable with the Tonna. I reckon I should get up to 3dB extra gain from changing the 2m antenna, and maybe lose 1dB on 4m.


The Sandpiper was so big and cumbersome that one of my neighbours noticed it and asked me what extra- complex tasks I was doing with that monster. Always wishing to minimise my impact on the local scenery, I decided to take it down. The Sandpiper is excellent, but not well made.

Laid on the grass after taking it down, the end of the Sandpiper shows the odd angles taken by the elements. This is due to poor mounting plates, and has been a problem all along.
The central mounting bracket on the Sandpiper had bent ...
 
So, this is what I am comparing these new antennas with - poor construction.

First the Vine. It is much more stable than the Sandpiper. The mounting hardware is vastly better quality. I have a Vine 3/4 element 4/6m dual band antenna which I used to use, and I was hoping for the same quality of material, and it delivered. It took about an hour to build. On the mast the Vine is stable and well balanced. Full marks for construction.

Secondly the Wimo. It also took about an hour to build. The Diamond which it replaced was good enough but I hoped for more gain from a longer boom. For some reason I had expected the Wimo to be over-engineered, rather like the Vine. However, it is not, it is a fairly light weight antenna. It is very well built, but not quite what I expected. What did I expect? Probably something huge and heavy like the old Jaybeams. It is not that, rather more like a better constructed larger version of the Diamond. So the boom does flex a bit when putting it up. However, it is beautifully made and I doubt if I will have any problems with it in the gales.

So up they went and the only major problem came when I pulled through some extra Ecoflex 10 cable for the 2m beam. Now that the 2m antenna is at the top of the mast it needed a bit more cable and I could draw some from inside the shack. Then I discovered a twist in the coax which must have been there since I put it in. Sorry, this is hard to photograph when you are up a ladder using a phone camera, but here it is ...
The braid is clearly buckled and I am worried that the carefully balanced impedence properties and low-loss nature of this rather expensive co-ax will be damaged. It must have happened when the co-ax was installed but it was just inside the house and invisible to my eyes.

There is nothing that I can do about it, other than cutting in a joint which is likely to make matters worse. Worse still, it is now outside the house, so any joint would be subject to the weather. Best leave it I think.

Anyway, once up in the air the SWR of both antennas is pleasantly low. I worked Henning OZ1JXY on 4m meteor scatter. I heard SP9HWY once but he did not hear me. On 2m the Wimo appeared to be receiving the NI beacon brilliantly well until I tried again an hour later and it had gone down in QSB.

We shall see. You cannot see the benefits of new antennas right away. It takes time. Certainly,  the Vine appears less "lively" than the old Sandpiper, but then the Sandpiper looked as if it was about to fall apart. The Vine is shorter and has fewer elements than the old antenna, so I could hardly expect it to be better.

Time will tell.

73

Jim
GM4FVFM

Monday 19 October 2015

A weekend on 40m, 12m, 10m, 6m and 4m ...

1) 40m
As winter approaches and the nights draw in, I am having more and more fun on 40m with my make-shift low dipole. This is the last 24 hours on WSPR with 2 watts (all bands, but it was mostly 40 on that day):-


I turned away from WSPR and towards JT65 and JT9 for periods in the late evening and early morning. I do like the odd QSO. On Saturday this brought W3WTE, WA4IAM (best DX at 5960km) and W1WJW, all on JT9. Also DX for me is TF2MSN, whilst only at 1494km, Iceland is not so common a country to work. By contrast, the following night just produced lots of very strong Europeans.

2) 12m and 10m
Surprise, surprise. I was about to give up on 10m. You would have expected 10m to last well into this winter, as the sunspot cycle slowly declines. And 12m should have lasted longer. But both went out about 2 months ago, with just the occasional DX spot since.

At the weekend they suddenly came alive again, with VK heard on both bands. Plus several trans-Atlantic spots too. As usual, click to enlarge the image, if you need to.


This gives me hope. With the flux index currently 120, there may be life in 10m and 12m for a while yet.

3) 6m
Now that the antenna was back up, it was time for wiring the rotator. As 40m of rotator cable (with plugs!) costs £100, I decided to re-route the cable to allow a 25 metre length to be used instead. To do this I have made a more direct route for the cables going to the second "6m" mast and the new rotator. This comes from the rotator, across to the eaves of the house, then along under the eaves to a new entrance into the roof space. The new entrance is a £2 ventilator bought from Poland via eBay.
So far the co-ax cables still take the longer route via the other ventilator, but someday I hope to re-route them too. Once inside the attic, the cable runs to a conduit which takes it inside the built-in wardrobe in the shack and on to the control box.

The point of using the ventilator is to stop insects etc getting into the house. I cut a small hole in the mesh to allow the cable through. Sadly, I had to cut the plug off the cable and join it inside, otherwise the plug was too big to pass through the vent.

I wrote a long piece ages ago (never posted)  blaming rotator manufacturers for being cowardly by using these big plugs on both the rotator and the control box. This allows them to get EU safety accreditation for the cable, but stops me pushing it though a vent. I cut it and joined it inside, so I have undone the safety accreditation.

So that is 6m sorted.

I was on the phone with Gordon G8PNN. He was asking about the 6m mast and it dawned on me that there is room there for a 70cm antenna. Gasp! UHF! Well maybe. Gordon reckons that 25m of Ecoflex 10 cable might work at 70cm. Ecoflex 10 is the coax I use for 2m and it is pretty easy to use. Up to now I have been put off by the expense and complexity of using even more difficult to work with cables over the longer cable route. It certainly looks like something worth investigating. Shortening the cable route by a good 10 or 12 metres brings reasonably priced cable into the reckoning.

4m
Back on 4m meteor scatter, I received an email from Henning OZ1JXY. He has been struggling for contacts even though we are in the (minor) Orionids peak season. This prompted me to come on and call CQ and up popped OH8MGK (KP23 1750km). Reflections were good and the QSO was quick. I also worked Henning.

Henning sent me a log of all the reflections he got from me over a day and he got almost every one. It makes me wonder could there be iono- or tropo- scatter between us as well.

I must do more meteor scatter.

Two points about meteor scatter
1) it is easy - ordinary equipment is enough, especially at 6m and 4m.
2) it is there almost all the time, almost all year. OK, better at certain times, but reliable at other times.

Summary
So there you are. Busy weekend on almost all my favourite bands. And a new 4m beam has arrived with a new 2m beam on the way. Something was happening almost all the time and now on Monday morning I have already had a 2-way with VK on 10m, and even 12m is turning up some spots.

I have also ordered a book at the weekend. It is an ARRL publication on propagation and radio science.  I wonder what light that will shed on things.

73

Jim
GM4FVM

Friday 16 October 2015

I am back and 6m mast replaced at last

Hi all, I am back from a spell in Northumberland.

Ages ago I decided to upgrade the mast supporting the 6m antenna. This mast started out as an experiment when GM4JR told me that he used two masts for various bands. This appealed to me as I often use 4m and 6m at the same time. At the time I was using a Vine 4m/6m dual band beam which was OK but a compromise. Better, I thought, to have separate beams (and the results proved me right).

The first version of this second mast was a lash-up to test it out. So it had a £50 TV rotator from Conrad (sadly they do not sell them any more) and that restricted me to 35mm diameter poles. It worked but it did whip about in the wind. So I decided upon a rebuild with proper 50mm poles and a new rotator.

The rotator, a Yaesu G-450 arrived but was jammed. £450 worth. OK, stuff sometimes doesn't work straight out of the box, so I am tolerant of that, but the supplier was useless. Several weeks were wasted trying to get it replaced. I phoned the supplier twice, sent two recorded delivery letters, e-mailed them three times, and travelled 180 miles round trip to return the thing in person. It still took weeks for them to reply to me and then they promised to ring back (and didn't). So eventually I got a new rotator, but I am changing my supplier.

I have got the rotator up (but not wired yet). I made a mess of getting the antennas up and the 6m one is very low, just about the roof ridge tile. I think it will stay there. I can do better, but while I was up there I forgot how to put it up properly. Not my best job, but it will do for now.
Above the 6m beam is the 4m ring-base 5/8th. It is higher than the 2m 3/4 wave which used to be up there. That part of the job, at least, went well.

Now I need to tidy up the cables and wire up the rotator.

I really should take the antenna down again and fix the flaws, including the lack of support for the 4m co-ax which might catch the wind, better strain relief for the 6m co-ax, proper height for the 6m beam ... but just for now it will do.

The Yaesu G-450 isn't a great rotator, but it is better than a TV rotator. Winter is coming and so are the gales. And I have nice 50mm pole on the bottom section at least.

Next task are the 2m and 4m beams on the main mast. I can tilt it over so they are less of an issue.

Northumberland was interesting. We did a long yomp to reach the waterfalls at Hareshaw. These were pretty but the hike up there fairly winded me.

I aim to do 10,000 steps daily (17486 yesterday), but that was about 16000 and all steeply up hill or down hill.

The caravan site was offering a "Dark Night" event for the Perseids meteor season in December. I was tempted to book BUT, to be frank their dark skies were no better than ours just 80 miles away in Berwickshire.

If I stay here for the Perseids, not only can I see meteor trails, but I can work DX using them. Plus I will be in a nice warm shack.

I took one of my Wouxun hand portables to the caravan but only used the telescopic antennas. I heard precisely one station in six days (on 2m), and he was a SOTA operator on a nearby peak. With very little VHF activity here I often feel hard done by, but it could be worse. I could be in Northumberland. Tee hee. Nice place though.

73

Jim
GM4FVM

Thursday 8 October 2015

VHF progress continues with coronal hole.

We usually think of sun spots and solar flares as generating radio action on Earth. Unfortunately there is not much going on there at the moment due to us being in the declining phase of the solar cycle.

Still, coronal holes can also produce interesting effects. Solarham warned us that a "middle latitude coronal hole is moving into a geoeffective position". By "geoeffective" they mean "directly facing us" on the Sun's surface and therefore most likely to affect Earth.

They weren't wrong:-


Number 10 there was right in the best location and I waited for it to take effect.

The solar wind measurements went off the scale early on 7 October but local time was about 09:00. At that time of the day the Earth's rotation puts the best area for radio effects at the other side of the world. The "auroral oval" has a break in it, and in the mornings the break is right over me. I had to wait for it to rotate (or the Earth to rotate under it) until the broadest part of the oval is right overhead (you can see an image of the auroral oval on Solarham taken from the Ovation observations).

The magnetometers went off the scale
and VHF opened up to classic distorted SSB and toneless CW. Aurora!

The K  number was 7, which is unusually high for a coronal hole disturbance.

There were beacons all over the place, from as far South as Dublin, East to Germany, erm Buxton (!), West to GI, North to Faeroe Islands and Norway ....

Just like during the tropo opening last weekend, OZ5AGJ was my first contact (how unlikely is that?) but this time he was on 70MHz rather than 144MHz. I stuck on 4 metres to work EI4KF and ON4IQ. ON4IQ was the best dx of the day at 700km, but his antennas were doing all the work.

Then I moved to 2m. Auroral contacts on 2m are different from 4m or 6m. The signals may be stronger, the antennas have more gain, but the distortion is worse on 2m. 2m is probably better for CW, but then my CW is not really up to is (I did call an SP station on 4m CW, but conditions changed).

On 2m I worked 5 Gs, GI4OWA, LA3EQ, GW8JLY and later GM0HTT. None of it great dx, but nice all the same.

This and the tropo opening makes me wonder if I would not do a lot better on 2m with a slightly better antenna. Certainly, the limiting factor on 2m here is the antenna, not the rig, the linear or the co-ax, which have all been upgraded over the past few years. My experiment with a 2m quad ended when I needed the space on the mast, and now I am back to my 10 element which has been here for years and is a bit bent. Come to think of it, the Sandpiper 6 element on 4m is looking sorry for itself too. I think that the last storm has condemned both of them to a spell in the garage.

No 6m this time as my 6m antenna is still down. A new rotator has arrived but after several weeks of wrangling with the supplier, only now does it work. So 6m has had to take a rest.

10 days, a tropo opening, a Sunday on 4m meteor scatter (yes, I eventually worked SP8SN in KO11 at 1686km), an aurora caused by a coronal hole, and the result is 11 DXCCs worked, pages filled in the logbook and a feeling the VHF is not boring.

Now, this coronal hole may return in about 26 days time, due to the rotation of the Sun. Then it might be smaller, but then again it might not.

73

Jim
GM4FVM

an expected solar wind sA middle latitude coronal hole is moving into a geoeffective position and an expected solar wind stream flowing from this zone could reach Earth by October 7th. Sky watchers at higher latitudes should be alert for visual aurora displays beginning Wednesday.tream flowing from this zone could reach Earth by October 7th. Sky watchers at higher latitudes should be alert for visual aurora displays beginning Wednesday.


Sunday 4 October 2015

At last, a decent VHF opening.

I have not forgotten you all, it is just that I am having dire rotator problems, more of which anon.

Since I moved here there have been perhaps 2 reasonable tropospheric openings. I mean the sort of thing which in the 1970s arrived every couple of months. A high pressure system moves in off the Atlantic and gets stuck over the North Sea or Scandinavia. It then sits there for four or five days, giving a widespread VHF opening over North West Europe. Here that means the local repeaters become full of people working on oil rigs in the North Sea, or captains of Icelandic trawlers, working with handhelds and reaching surprised locals driving along the road from Selkirk to Peebles.

Surprised locals of course, because otherwise the repeaters in this region are virtually entirely unused.

So we have just had such an opening. I might as well go over it all as it is such an unusual event.

As a reminder I do not have a very fancy 2m station, IC7100, Microset linear 200W peak, 10 ele at 10 metres. On 4m it is the same rig and a TE Sytems linear, 100W peak, and a 6 ele yagi.

On 27 September we had the "Practical Wireless" 70MHz contest. I worked 8 stations and nothing particularly remarkable was apparent.

By 29 September the pressure was about 1026 and rising. The RSGB 70MHz "UK Activity Contest" was more lively than usual. I worked 15, reaching G0HEL in IO81, which is 510km. Interesting, but hardly my best DX in these contests. Still, as the RSGB contests are often held at times when the conditions are poor, this was not bad.

By 30 September pressure was tending to 1028 mb (it reached 1032) and I worked OZ5AGJ in JO55xe on 2 metres SSB at 14:07. Once again not great DX at 678km, but loud 57 reports both ways. OZ on 2 metres is DX in my book. From that point until 3 October I could hear one or more Swedish beacons, SK1 (or 6 or 7)VHF. Then at 20:24 came OZ6TY (JO55 890km) and at 22:26 SM7GVF (JO77 1029km).

I like them all, but once they go over 1000km, I like them more.

Despite many attempts by me to raise anyone on 4 metres, this was a 2m event here. I heard some 4m beacons, but no contacts resulted.

The Hepburn Tropo Index site can be very useful in these conditions. Updated every day at about 18:00, for many many years this very handy site translates forecast weather conditions into propagation predictions. OK, you could get something similar from a weather chart if you knew how to interpret it, but Hepburn's chart does all the work for you. You can jump forward by clicking it, for about five days, with more regular updates for the next two days, and more general predictions for future days.

Here is the Hepburn chart for 1 October.

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You can see the effects of the high pressure centred somewhere over Denmark by that stage. To work tropo you tend to do best by beaming to one side of the peak high pressure, so in this case Northern Germany looks like a good bet, though sometimes right through the middle works too.

Tropo openings are usually quite different from, say, Sporadic E ones. With Es you are using a small area of ionisation midway between you and the dx to reflect your signal. Therefore you hear only one station, or a few grouped together (that is a huge generalisation, but roughly true). With tropo you need to have the high pressure right along the path you are using (again a generalisation), and you need to be under the raised pressure and so does the dx station. That means that generally you hear stations all around the high pressure area.

A troposheric duct is a bit different, as it is more like a tunnel between you and the dx, where you only hear a few stations.

This looked like a classic tropo system, but actually it worked more like a series of ducts, and I was hearing a few stations at a time, and the area covered was moving around. Mind you, it did last four days so it would move a bit.

On 1 October I started off working DL8VU (JO54 814km) before working 3 more stations in Germany and one in Sweden. Best dx that day was San, DD3SP (JO72 1131) who I have worked now on 6m, 4m and 2m. San was best dx of the whole event for me.

On 2 October I worked Marek SP1JNY (JO73gl 1101) - a part of Poland closer than San's part of Germany. Then it was 1 Netherlands, 5 Germany, 1 Sweden.

By 3 October the high pressure was drifting away. I heard more Germans and Swedes, and beacons in both, but no contacts resulted.

This looked like a classic tropo opening, but it was not quite like that. The area of high pressure was further North than usual, so the normal opening into Netherlands, Belgium and France did not occur. Also, it was pretty localised and moved about a lot. Still, Denmark, Germany, Sweden, Netherlands and Poland are not everyday fare here. I am happy with that.

Best of all of course was a series of rag chews with Rob PA3GFY, David GI4SNA, Robert GM4GUF, and others. Whatever dx there may be, these long rambles are always interesting. And when I was blethering with John GM4EOU across the Firth of Forth in Cellar Dyke, DL8VU chipped in for a 3-way contact that lasted almost 20 minutes. There was more QSB on the path to Cellar Dyke (there usually is none!) than there was to Germany.

And thanks go to Chris GM4ZJI whose constant helpful SMS texts and phone calls kept me on the path of the dx.

Yes, I heard LY2WR in Vilnius KO24fo 1861km but not quite strong enough for a QSO. So a new DXCC heard but yet to be worked.

All in all a great few days. I know tropo is best in the early evenings, but I managed to still have a time to sit in front of the TV in the evenings, and work some DX.

Back to normal today (4 October). Meteor scatter with SP9HWY on 4 metres. Now, this I enjoy too - 1538km is more like the thing really. Big openings are just great, but working an old pal miles away  is good too. Just as well, as flat conditions are what we have most of the time. And now I hear SP8SN which would be a new square if he could hear me!

Will it be years before the next tropo opening? I suspect so.

Am I bothered? Not really.

73

Jim
GM4FVM

Tuesday 15 September 2015

Anytone AT-588 - new 70MHz FM rig and antenna

I have not managed to work any 70MHz (4 metre band) FM DX this year.

This is disappointing. The plan was that my 4m vertical, a Sirio J-pole, would go on top of my 6m HB9CV. But when I stood up there trying to locate the pole with the beam and the hefty 4m antenna, I decided that it was just too heavy and bulky to fit. I was using a 1.5 inch pole and a TV rotator, and it just seemed to much weight for both of them. So I tried the 2m Watson X30 on that pole and it was far lighter and easier to fit, and it will catch less wind than that long Sirio. So the Sirio antenna was left to site somewhere else.

Deleting five paragraphs of explanation, let me skip several months to the point where I found that the Sirio was not working properly, and neither was the coax which fed it. So I have put up a Sandpiper 5/8th with a ring base on top of my main mast, until such times as it can go up above the 6m beam. This is at the risk of blowing up the GaAsFET front end on my SSB set-up, or perhaps the 100W from the SSB set-up killing off the 4m FM rig. Putting two antennas on the same mast, feeding two sensitive rigs on the same band is a risk, but so far so good.


Anyway, the 5/8th works 100% brilliantly on the same pole as the yagi.
Hopefully it will last there until the other mast is ready to take it. It has a ring base, so it is quite difficult to see the "ground plane", and hopefully the 4m yagi will not "see" such a small horizontal metallic ring right above it.

Having got all this underway, I heard that the 4m Anytone AT-588 was available again. The small low band rig can run up to 50W and gets great reviews. So I bought one, and the supplier was excellent. He is based in Ballymena in GI, and he sells them on eBay for the princely sum of £118, and offers a personal service. Not only does he test each rig, he sends it by next day delivery, and he checks to make sure you are happy that they work. He only imports small batches from time to time, and they sell out very quickly.
The AT-588 may be more familiar to many as a 2m or 70cm rig, and it has appeared in those versions from time to time. This low band version has all the features of the others, including tone burst, repeater shift, DCS, CTCSS ......

So why do I need a new 4m FM rig? Good question. My existing Anytone AT-5189 has given many years of troublefree service, but it is not the easiest thing to use. For example, to alter the volume you have to push the channel control and then adjust that knob, which is not easy when you are trying to work someone (I kept changing the channel by mistake and losing them). The AT-5189  is clearly built with PMR use in mind (taxis and commercial vehicles). Selecting scan required four button presses and selecting a menu item, but then not many taxis scan the band.

On the other hand, the AT-588 user's manual starts with an explanation of how to use it for amateur stations. The 588 has a proper volume control, a better display, and a wider selection of useful options on the microphone keypad. And unlike most PMR rigs, the 588 has the S meter which the 5189 lacks. Well, S meter is not the right name, but four LED blocks, which is as good as most FM rigs these days.

I am not sure how useful 50W will turn out to be. The rig gets quite hot on the highest power. I have positioned it to get some benefit form the fan I have on the FT-817. Until I move the antenna onto a separate mast, I will stick to 25W to spare the FET in the pre-amp on the SSB rig.

The size comparison between the two Anytones is quite striking. No doubt moving the loudspeaker to the top rather than being forward facing makes a big difference to the layout. The newer rig is on the top:-
The new AT-588 is deeper, but that is not a snag in any application I am likely to use:-


Initial contacts suggest that the AT-588 maintains Anytone's reputation for sensitive receivers. Both of them are maybe a bit TOO sensitive, as both rig can be overwhelmed by HF WSPR transmissions in my shack, but then plenty of rigs have problems with that. I do insist on transmitting on three bands at once.

Most 4m FM rigs have an ancestry which can be traced back to commercial rigs rather than amateur roots. And so the otherwise excellent AKD/Garex/Spectrum rig started out as a marine transceiver, and both of these Anytones are clearly derived from PMRs. My Wouxun handhelds are the sort of thing you see on construction sites. However, all these modern rigs seems to perform much better than the old converted PMRs we used to use. From Pye Cambridges to Philips FM1000s, they were discarded after years of use and were old technology when we got our hands on them. At least these ones are modern and well equipped.

I am not sure whether to let the AT-5189 go in a sale or locate it in my car. It would certainly perform better than the handheld in the car, but permanent fixings are not easy to find on modern dashboards.

And finally a word of warning. Don't make the silly mistake I made.

Don't change the coax, the antenna and the rig all at once. Then if you cannot hear someone (because he has turned his power down and forgotten to put it back up, but I didn't know that) you won't know what to fix. And you might end up changing everything, only to find that the main problem was at the other end.

73

Jim
GM4FVM