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

Saturday, 24 October 2015

India, and GI4DOH's propagation predictions

I have been enjoying popping up on 40m around dawn and dusk to see what can be done with my simple wire antenna for that band.

I was amazed to have my first CQ on 20 October at 21:31 answered by VU2ABS. OK, he came back with a -27dB signal report (!!!) but I called on low power and I later shoved it up to about 50 watts for the end of the QSO. I gave him -13dB and the QSO went according to plan. By this I mean it took the standard JT65 mode minimum of 4 minutes, plus an extra minute each for him to request a QSL and for me to thank him for a new DXCC on 40m. No need to repeat any detail and signals were perfectly stable.

Now when I report something like that I am not trying to "big" myself up. I did nothing special. I am just reporting that I am surprised how well a low dipole is doing for me. Everything else might be fancy beams and towers, but the 40m set up is just two bits of wire. To say that I was taken aback would be an understatement. Yes, I have been heard regularly further away on WSPR, but WSPR is a beacon mode and takes 2 minutes to send a very limited amount of information. This was a proper QSO.

So I was pleased with 8349km on 40m, and next night netted UA9CR (MO06 3762km) and AI4VR (EM64 6608), which made me pleased too.

Surprise is certainly my reaction. A local OM heard of what was going on here and said that he did not take up 40m at present as he would not have room for an efficient antenna. I know what you mean, but it looks like an inefficient antenna does good work too.

Of course, any antenna (however inefficient) has an infinite gain figure over no antenna at all. So I suppose it all proves that just getting on and doing something is always better than not doing anything.

GI4DOH posted here a few days ago that the solar flux index looked to stay above my magic 100 level for a while. So I decided to test out his predictive powers. With the official forecast for 10m propagation as "poor" I set up WSPR to run early on 23 October. Was the official view right that it would be poor, or was Richard right that there was hope of DX?

Make up your own mind from the table below, but I have to admit that I know who I am going to have to listen to in future, Richard ...

Time    Stn              Freq            Rpt       Locator     Pwr dBm/W   Heard by     Locator      km

08:30  GM4FVM  28.126082  -15  0  IO85wu  +33  1.995  VK2KRR  QF34mr  16748 
08:28  LZ1OI  28.126044  -16  -1  KN22jc  +40  10.000  GM4FVM  IO85wu  2463 
08:28  VK3KCX  28.126081  -11  -1  QF22qd  +40  10.000  GM4FVM  IO85wu  16884 
08:26  VK2KRR  28.126175  +4  0  QF34mr  +40  10.000  GM4FVM  IO85wu  16748  
08:24  RA3APW  28.126112  -17  0  KO85uv  +20  0.100  GM4FVM  IO85wu  2450 
08:22  VK3KCX  28.126082  -11  -1  QF22qd  +40  10.000  GM4FVM  IO85wu  16884 
08:18  LZ1OI  28.126047  -22  -1  KN22jc  +40  10.000  GM4FVM  IO85wu  2463 
08:14  VK3KCX  28.126082  -9  -1  QF22qd  +40  10.000  GM4FVM  IO85wu  16884 
08:14  RA3APW  28.126112  -27  0  KO85uv  +20  0.100  GM4FVM  IO85wu  2450 
08:14  VK2KRR  28.126176  -2  0  QF34mr  +40  10.000  GM4FVM  IO85wu  16748 
08:12  GM4FVM  28.126083  -22  0  IO85wu  +33  1.995  VK2KRR  QF34mr  16748 
08:12  GM4FVM  28.126106  -23  0  IO85wu  +33  1.995  VK3KCX  QF22qd  16884 
08:08  VK3KCX  28.126082  -4  -1  QF22qd  +40  10.000  GM4FVM  IO85wu  16884 
08:02  G0JEI  28.126008  -27  0  IO93ic  +37  5.012  GM4FVM  IO85wu  310 
08:00  VK2KRR  28.126177  -5  0  QF34mr  +40  10.000  GM4FVM  IO85wu  16748 
07:58  VK3KCX  28.126082  -1  -1  QF22qd  +40  10.000  GM4FVM  IO85wu  16884 
07:52  GM4FVM  28.126112  -22  0  IO85wu  +33  1.995  FR1GZ  LG79rc  10097 
07:52  GM4FVM  28.126084  -19  0  IO85wu  +33  1.995  VK2KRR  QF34mr  16748 
07:52  GM4FVM  28.126107  -21  -1  IO85wu  +33  1.995  VK3KCX  QF22qd  16884 
07:50  VK3KCX  28.126082  -8  -1  QF22qd  +40  10.000  GM4FVM  IO85wu  16884 
07:50  VK2KRR  28.126176  -3  0  QF34mr  +40  10.000  GM4FVM  IO85wu  16748 
07:42  VK3KCX  28.126082  -11  -1  QF22qd  +40  10.000  GM4FVM  IO85wu  16884 
07:36  VK3KCX  28.126082  -12  -1  QF22qd  +40  10.000  GM4FVM  IO85wu  16884 
07:34  VK2KRR  28.126177  -16  0  QF34mr  +40  10.000  GM4FVM  IO85wu  16748 
07:30  VK3KCX  28.126081  -25  -1  QF22qd  +40  10.000  GM4FVM  IO85wu  16884 
07:20  VK2KRR  28.126177  -18  0  QF34mr  +40  10.000  GM4FVM  IO85wu  16748 
06:54  GM4FVM  28.126112  -25  0  IO85wu  +33  1.995  FR1GZ  LG79rc  10097 

WSPR is not a QSO mode, but a report of -1dB means that an easy QSO would have been possible.

Since then I have gone on to make quite a few QSOs across the Atlantic but VK is always hard to beat. Thanks for that piece of wisdom.

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.


Wednesday, 7 October 2015

CQ DX (on Echolink?)

Echolink is one version of various systems which allow internet linking of radios.

I am not against it, it just doesn't count as radio for me.

It is radio from station A to an internet linked repeater, and then from some other interlinked repeater to station B. And between the repeaters it is internet. Repeaters or gateways or voice nodes or whatever we call them today.

So, supposing some station wanted a chat with me about something, then why not use Echolink. No problem there, but it is not radio between us, it is the internet for most of the journey. I guess I have used Echolink two or three times. I even used my mobile phone at one end of the contact.

Personally, I cannot claim an Echolink contact as DX. Mostly, I don't use it of course, but apart from that the effort is the same working the repeater (which is 2 miles away) and working New Zealand. There is nothing for me to celebrate or note in working DX. Once you have worked the repeater you can work anywhere.

Of course the people who mastermind the repeater and the link get good experience and learning opportunities, and we all learn about how radio now works for most commercial applications.

If amateur radio is to remain the learning forum for lots of technologists of the future, they can use amateur radio to learn about internet linking (if they want to).

But essentially I can give it a miss.

Then I noticed a DX cluster posting for these contacts

Top 250   144 MHz   UTC   Spotter   Comment  
SK4MPI   144412.0   07 Oct 09:52   RM1A   56a
NO2A   145662.5   07 Oct 09:50   LA1YKA   59 Echolink

Erm. Someone in Norway posting that he worked USA via Echolink. Ahh, that hardly made me jump to my dial to see if conditions still existed to do the same. Or see the need to improve my station, antennas, or operating procedures to find out if I could do it too.

Echolink is fine. But in my book it isn't DX. Not as much as the contact above it in the listings, where a Russian is hearing a Swedish beacon via Aurora. There is a large coronal hole pointing towards us, and this is creating auroral conditions. I need to step up for that. I need a good station and cunning plans to work an aurora. Not Echolink.

I am not calling for it to be stamped out. I am not against internet linking. I just don't need it, any more than I need RTTY or (insert any mad plan)-on-the-Air. Everyone is welcome, but I think we each can have a personal view about what is DX, and what matters in radio experimentation.

It is a personal thing, and I am a person too you know.

73

Jim
GM4FVM

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.

-----------------
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