Tuesday, 12 October 2021

FVM versus the residual current device.

Sorry I have been absent for a while. This has been due to work pressures and a bit of a medical issue which hopefully should be resolved soon.

I have been having a problem keeping my mains electricity on. The mains distribution board was receiving me infinity dB over S9.

When I started using my Tajfun 70cm amplifier I started to have issues with RF tripping protective circuits in various mains circuits. This was not such a big issue, but it really became crucial when it was our own trip that was going. 200W of RF would trip our main residual current device - RCD (also called a ground fault interrupter in foreign parts). This caused me to limit power to 100W on 70cms and think a bit more about it.

I have looked a various websites and I found almost no references to amateurs tripping mains electricity protection circuits. There were a couple of references in the US going back ten years or more, but they affected only one make of device, not a 240V one of course, and not 70cms, so they did not seem relevant.

A few tests proved pretty conclusive. 200W would cause it to trip if beaming that way, and it was instantaneous. If I let the first few moments of transmission pass at low power and then increase the power back to 200W it did not trip. This suggests that there is a spike from the radio (an IC7100) which is momentarily over driving the linear. But, whatever, the RF was clearly tripping the device. Erm, in my view anyway.

I asked a few people who know about mains electricity and they doubted that RF could do such a thing. Nevertheless, I reckoned it was the RF. I just parked the problem as there was plenty going on, and 95W on 70cms seems to be doing all right for me if I stay off moon bounce. The problem is compounded as the beam heading where the moon generally rises passes the point where the RF cuts the mains power. So no EME at high power, with the Tajfun sidelined and my old 95W Microset back in use.

An added point was that as the FVM house is divided into two mains circuits each with its own independent RCD, and only one half was tripping off. As luck would have it, the half which does cut off is not the half powering the shack, so I motor on without being aware that Mrs FVM's machinery (dunno what, I guess sewing machines and irons, plus the TV), has got cut off. This seemed to cause some strife, but I cannot understand why. The radios kept working, so everything seemed pretty well OK to me.

Proteus residual current device at GM4FVM (on the right, others are circuit over current trips)

All went well in the sense that I was ignoring the problem (because people who knew about these things told me I was imagining it), until I renewed my correspondence with Scottish Gas. I might explain that I stopped being a Scottish Gas customer years ago when I transferred my contract to another, cheaper, provider. Generally I was not greatly impressed by their service then. About a decade later I changed my provider again to one called "Robin Hood Energy" hoping that Robin Hood was no longer the ruthless bandit he used to be. Sadly, after three weeks, Robin Hood Energy ceased to be, causing all manner of headaches for the taxpayers of Nottingham City Council, who owned the operation.

This was before the current disaster whereby the UK government has set a maximum price for energy supplied to the public which is lower than the suppliers can buy it for, which not surprisingly is driving many suppliers out of business. Back when Robin Hood went belly-up there was some semblance of order in the market and my account was transferred to another supplier - guess who - Scottish Gas - on existing terms. I got some slight compensation that I still got the same price terms from them as I had been on at Robin Hood, which was a lot cheaper than I could have got from Scottish Gas 3 weeks earlier. So I have two years to enjoy that.

In due course British Gas informed me that my mechanical meter was outdated, liable to be unreliable, and I must change to a new mechanical meter. At the same time Scottish Gas tried to persuade me to change to a "smart meter". This is not a mistake by me, they call themselves British Gas when giving bad news (pay your bill, change your meter) but Scottish Gas when they are giving good news (have a free smart meter, isn't life good?). They are, of course, effectively the same organisation as they are both owned by Centrica. Anyway they said that I need to change it, though it does not seem so long since it was last changed. A smart meter will send readings wirelessly to the supplier meaning I would not need to take manual readings (if it worked ...)

Mechanical meter at GM4FVM, which seemed to be fine to me.

Faced with changing the meter anyway, I opted for a smart meter after news in the RSGB magazine that there was little risk of it causing RFI to my radios. A pleasant chap from Scottish Gas arrived, fitted the new "smart meter" and it promptly tripped the RCD. Many tests, same result. It was clear to me that the RF was to blame, as it had been before. After discussing the possibility of re-fitting the mechanical meter we compromised by his agreeing to temporarily isolate the RF side of the smart meter and promising to return.

Scottish Gas smart meter at GM4FVM, meter on the bottom, "Communications Hub" RF unit on top.

I spoke on the phone to a "bigger man" at Scottish Gas who ran through what he thought might be happening. He still thought that some small earth leakage must be happening which was rendering the RCD liable to trip. As the smart meter is up stream of the RCD it seemed to me to be unlikely that it was earth current which causing the tripping. After all, the smart meter is not in the circuits protected by the RCD (and neither are my radios).

Anyway, I contacted an electrician with a view to having the RCD replaced. He asked for a photo of the RCD and promised to replace it the following week. I never heard from him again.

In order to find a trustworthy electrician I used the tradesman's network instead. I asked a house painter in the village to recommend an electrician. This worked brilliantly. The guy he suggested turned out to be knowledgeable and very willing to change the RCD if I wanted to. However he suggested that I go instead for equipping each circuit in the bank with its own combined current trip and RCD. He would then isolate the old RCD. This seemed like a perfect solution to me because if there is some small earth leakage then I can narrow it down to one circuit and maybe not knock off the TV, which seems to matter more than anything else for some reason. He arrived within days and did the work neatly and cleanly.

New arrangement, separate earth protection on each circuit, main breaker now isolated.

You can see from the photo that the RF Communications Hub unit on the smart meter, the thing that makes it "smart", is right below the distribution board. The inverse square law means it was getting lots of RF from the wireless unit right below. It seems certain to me that it was RF from that unit which was affecting the RCD because now that the RCD is isolated the tripping has stopped. My RF has no effect on the new arrangement at all.

In due course, Scottish Gas returned to turn on the radio or "wireless" side of the smart meter which should have started sending readings to the Scottish Gas system to update my account.

I might add that since the system has been fully activated in smart mode it has has not worked at all. My Scottish Gas (a.k.a. British Gas) account is showing zero readings, so nothing is reaching them. I have activated their app which is designed to work with the smart meter and it shows no readings either. What point a smart meter is which does not relay any information I cannot say.

It cost me £250 to upgrade the distribution board ("fuse board") for half my mains system to allow for a smart meter which doesn't work. On the other hand it is not RF sensitive. Next task no doubt is to replace the other half for another £250, though it has been no trouble --- yet.

My Granny always told me to avoid people who change their name depending on what suits them. I thought she meant rogues, vagabonds, or the Duke of Rothesay. I now know it applies to British Gas and Scottish Gas too.





Thursday, 9 September 2021

Signs of Autumn at Ayton

You can define autumn several ways, but some say that autumn starts here on 1 September. I always judge it by the arrival of the harvesters and the removal of the golden sea outside the shack window. This time though they arrived at the end of August.

The significance of this time of year for radio is that this tends to mean the end of the peak Sporadic E season. Sporadic E carries on of course, and it can occur at any time of year. I will be keeping a close look out for more Es, but the main season is now over. Not only is this according to the calendar but according to my radios which have fallen silent on 6m and 4m.

I get the impression that 2021 was not the greatest Sporadic E season. Certainly it was not great on 4m, where most openings were confined to southerly directions for me. The traditional eastern direction did not deliver as much as usual. I am not complaining of course, as I have worked 9K2YM this year.

Funny enough, as the harvesters roll and the Es season comes to an end, there is often a tropo opening here. It happened last year. And it happened again this year.

The odd thing about this year's harvest tropo opening was that it lasted for two weeks.

Yes, from 22 August to 4 September 2021 there was a series of tropo openings from GM4FVM. They came and went, sometimes opening towards Norway and Sweden, sometimes towards Spain, usually somewhere in between. Not really an opening, more a series of openings. There were few contacts to ON and PA, but as I say I cannot complain.

I worked a new country on each of my higher bands, 2 metre, 70 centimetres and 23 centimetres. Plus dozens of other stations. So I should be happy with that. And so I am.

1296MHz contacts at GM4FVM 22 August to 4 September 2021

As you can see (though you might need to click on the image to make it larger) I only worked three stations on 23cms, and the openings there only lasted for 3 days. One of the three was worked twice on 23cms.

Nice contacts with Niels OZ2ND and Jaap PA0O were much appreciated. In fact, Jaap replied to a random CQ I sent, which is the first time that has happened to me on 23cms. First prize went to LA3EQ for giving me a new country on 23cms in the shape of Norway. Not that I even realised that I had not worked Norway. I had forgotten that this country, along with several other nearby ones, was still missing.

Three stations on 23cms add up to a good haul and best DX of 690km was good going. Somewhat annoying was hearing a station at 900km distance who couldn't hear me. At the moment I am lacking in power. The linear I had on loan has developed a fault and I was back to 60 watts. Another time maybe.

432MHz contacts at GM4FVM 22 August to 4 September 2021

 On 70cms there was activity for the entire two week period. I was really pleased to work 20 squares and 10 countries. There was a time when I could only dream of 26 QSOs on 70cms never mind completing them in two weeks. SP1MVG was best DX at 1097km, but also a new country. Once again, like Norway on 23cms, I did not even realise at first that I had not worked Poland on 70cms. EB1B was heard on 70cms but I could not reach him.

At times I found 2m to be far too hard to keep up with. The openings were swirling around and there was a lot of QSB. Many QSOs were easy to start but hard to complete. For long periods I gave up on 2m and concentrated entirely on 70cms and 23cms. Who could have predicted that a few years ago?

144MHz contacts at GM4FVM 22 August to 4 September 2021

What a fortnight! 112 QSOs and even one on FM (G1ZJQ/P), but nothing at all on SSB even though I looked every day. 56 squares and 16 countries with a best DX to SP3N at 1406km. Always a joy to work Spain with EB1B now joining EA1HRR as something of a regular.

Then of course was the new country on 2m. GJ3YHU made it country 43 on 2m.

Any tropo opening is good fun. This one was certainly unusual being spread over 2 weeks. At some stages I got frustrated by how difficult it was to complete a QSO on 2m. As usual stations in the 700-800km become more interested in working further than me, and who could blame them? On the other hand it is very hard for me to work beyond that distance to the East, North East and right round anti-clockwise to South. This is not anyone's fault, it is another aspect of me being located on the "edge of Europe". Still, I enjoyed sitting here listening to Swedish and Norwegian stations working into France, Ireland and Wales.

It is also a pleasure to work stations during these openings who are located closer to me. A good many stations located in valley bottoms and behind hills can suddenly work much further afield during a tropo opening. As a reward for their patience I am always happy to give away a new square to them if they need it.

There is no perfect location. Even in Central Europe, where contacts appear to possible in all directions, there is a lack of the sea paths I use regularly. And of course activity is lacking to the East for them too.

The harvest 2021 openings are over but there will surely be more in the future.

Here is a strange development. I have started to use a digital voice hot spot. As with my failed plan to use network radio or Echolink as a sort of intercom to other interested radio amateurs, I have now decided to try DV. So far I have got D-Star running and I am trying to get DMR going now too. DMR is not easy to set up. I will report on that later.

I feel that the snag with this Digital Voice plan is that almost nobody uses these aspects of amateur radio to talk about amateur radio. I must not judge it before I have tried it. However, from what I have seen so far I am not optimistic. The technology works, but is there anything there to justify the effort?

More later on this I hope.

Farewell to Summer and the peak Sporadic E season. Welcome to harvest season. Let us hope for a mild, tropo-opening rich, and solar activity packed, Autumn.

A harvester piles up the stalks for the baler, outside GM4FVM's QTH.




Friday, 13 August 2021

A bit of meteor scatter and trans-Atlantic Es.

I have not been well.

Mrs FVM and myself headed west to enjoy a few days relaxation in far-off Kirkcudbright. We both fell ill with tummy bugs.

I have spent the last week with a bad case of what Granny Edgar would have called "The Skitters".

It got really bad at times. How bad? Doctors ask you to rate the pain in a scale from zero to ten. I cannot really do that, but it got so bad that on two occasions I looked at the radio, saw good conditions, and had to go back to bed. That is about as bad as pain can get in my book.

During long spells bent double with stomach cramp I had plenty of time to sit and consider the woes of the world (in addition to mine). I did a lot of sitting. Apart from the obvious, I found that standing resulted in falling over followed by lying down wondering what was going to happen next.

Being a normally mild mannered chap and not given to fulminating about things that annoy me, I was for once overcome with anger about aspects of my hobby. Perhaps it was the badness coming out in me.

I did write it, but I have deleted it. Sure, there are some things about this hobby which infuriate me but do I need to go on about them all here?

In summary, once anything in amateur radio becomes popular, people start attacking it. And once something becomes less popular, articles are written about how we should support this dying thing, whatever it is.

I have never encountered a hobby which spends so much time knocking the things in their interest which are growing, and blaming us all for not supporting some outdated, boring, inefficient old irrelevant aspect of it.

I will return to this I am sure.

Right, moving on for now.

The Perseids are near their peak and as usual I have been doing a bit of operating. Mostly listening I have to say, but a bit of transmitting too.

I even ventured on to 2m. I should say that I rarely do 144MHz meteor scatter these days because I find it much too much effort for very little reward. Not only have I worked so many squares over the past few years with Tropo and Es, but the QSOs are often very long and many are never completed. Still ...

144MHz meteor scatter QSOs at GM4FVM 1 to 13 August 2021

Click to enlarge images as usual.

Granny Reavey, on the other hand, used to say "Needs must when the Devil driveth". This seemed to mean that when you need to do something you may be forced to follow the path of the Devil, the Devil in this case being 2m meteor scatter.

Interesting Granny words these, "Skitters" and "Driveth"

What was driving me into the hands of the Devil here was the presence of UA2FL on 2m. I had not worked Kaliningrad on 2m before, though I did narrowly miss it once on Es (recorded somewhere in this blog). So I saw him and tried for four days before he came up into the clear and I worked him.

Working OH6HFX at 1673km is pretty satisfactory too, but UA2FL at 1470km brings the 2m country list to 42. And while I was working Slava I was called by SP2ERZ for an unusual "double", as  I worked ERZ on 4m and 2m one after the other which must be my first meteor scatter double. I did look on 6m for him but there is no MS treble here (yet).

Looking at my all-band meteor scatter list so far in this year's Perseids you can see my preference for 4m and even sometimes 6m:-

All band meteor scatter QSOs at GM4FVM 1 to 13 August 2021.

16 QSOs, 1 on 6m, 9 on 4m and 6 on 2m. How so?

Because the length of time the ionisation trails persist decreases with frequency, the pings get shorter as you go up the bands. So 2m contacts take a lot longer to complete than 4m ones, which in turn are longer than 6m (and if you go to 10m the ionisation can last so long that contacts are often mistaken for Es). 

Which makes 2m meteor scatter a bit of a pain for me (more pain Jim?).

The result is that a contact can last for an hour or more, during which time you are transmitting a signal into the unknown and waiting to see if you get a ping back to confirm that it has been received. No ping in reply does not mean that you have not been heard, indeed on 2m it often just means that you are not hearing the reply. Or vice versa ... you are rather left in the dark.

So to give an example the QSO with UA2FL went like this:-

11:37:00 I heard UA2FL calling CQ.

11:37:30 I called UA2FL

11:38:21 I received his report -02

11:38:30 I sent my report R +08

I kept sending R+08 until

11:53:02 when I heard him send RR73.

At that stage we were 16 minutes in and I had all I needed.

11:55:30  I sent him 73

I kept sending him 73 on and off until 12:50:30, which was almost an hour after I had first heard his RR73

The reason why I kept sending 73 was because during that hour, every ten minutes or so, I got his signal saying RR73, which meant that he still had not got my 73 signal. If he was still sending RR73, I felt I needed to keep sending him 73 to confirm to him that I had got his RR and that the QSO was complete. I guess he never heard my 73. I will never know unless I get a QSL card which says so. I do know he got my report and that is all I need at my end. He does not need my 73 to confirm the QSO, just to know it is complete at my end.

The thing was, as far as I was concerned the QSO WAS complete. I just had no way of telling him that, apart from sending him 73. Due to the random nature of meteor scatter he never seemed to get my 73, and he just kept going - no doubt waiting to receive it

Let us be clear about this, UA2FL was doing the right thing. I admire his patience as many other operators would just have given up and waited to see if they got a QSL card. 

Contrast this with a QSO with Ivan, S51DI, a stalwart of 4m operations. I have worked him dozens of times so no need to send my locator and save 15 seconds! :-

210812_164505    70.174 Rx MSK144   0  4.9 1553 CQ S51DI JN76
210812_164515    70.174 Tx MSK144   0  0.0 1500 S51DI GM4FVM +09
210812_164530    70.174 Rx MSK144   3  0.5 1553 GM4FVM S51DI R+08
210812_164545    70.174 Tx MSK144   0  0.0 1500 S51DI GM4FVM RR73
210812_164603    70.174 Rx MSK144  -5  2.6 1556 GM4FVM S51DI 73

Whole QSO completed in 58 seconds.

So just to put these beside each other - 2 metres took 1 hour and 13 minutes, 4 metres took 58 seconds.

The UA2FL QSO took longer than usual. OK1GU took 42 minutes to complete, still a lot longer than the 58 seconds. But 2m QSOs can sometimes take hours to compete.

The shorter and weaker 2m pings are not the only reason for this. The tx/rx period commonly used on 2m is 30 seconds, whereas on 4m and 6m it is 15 seconds. The reason for this difference is presumably rooted in the times when MSK144 was introduced to replace FSK441. FSK had a 30 second period and to avoid problems in the changeover it was decided to use 30 seconds for MSK. Yet on the other bands MSK just used a different frequency and everybody went over to 15 seconds. It used a different frequency on 2m too, so that whole argument is a bit doubtful.

I was contacted at the time by an amateur who thought that I should be campaigning for a 30 second period. I am not in the business of doing campaigns. It is not my job to tell people which period to use on 2m MSK. That is entirely up to them. They have that right, even if they are making a mistake.

There is no advantage to using 30 second periods, apart from the historic changeover period from FSK (which could have been handled differently anyway). The signal length on MSK is 72 milliseconds, so repeating it for 30 seconds makes little difference to repeating it for 15 seconds. On either system you are still transmitting for 30 seconds out of every minute. However, there is a distinct disadvantage in probability terms to using the longer period. This is due to the likelihood that the path for a signal back from a dx station being open is higher immediately after they see your signal. This is because meteor often come in showers and the ionisation will last for a certain length of time. The shorter period offers a probabilistic advantage for making shorter QSOs, or completing QSOs which would otherwise be unfinished.

The advantage extends to periods shorter than 15 seconds, and I have seen people successfully using 5 second periods. This makes the 30 second periods on 2m look a bit daft. It is true that the advantage from using shorter periods is greater at lower frequencies, but it is still a factor at 144MHz.

I have sat here and watched a full 30 second meteor burst on 2m while waiting to reply to a station - on 15 second periods I would have half the QSO completed by then.

It is not for me to try to change any of this. People have fixed ideas and each amateur is free to choose what they do. It is just a pity when they chose a standard for 2m which actually disadvantages their own efforts, when 4m and 6m can prove that there is another way. Some 4m and 6m QSOs take a long time too, but that is not self-inflicted. MS is all about probabilities and not certainties.

So I will probably continue to give 144MHz meteor scatter a wide berth.

Unless the Devil drives me toward another new DXCC.

Incidentally, the single 6m MSK QSO was to YT9A in KN04, a distance of 2003km and probably my most distant meteor scatter QSO ever. Also it was done on 100W barefoot and took only 75 seconds to complete thanks to 15 second periods...

210808_114430    50.313 Rx FT8    -12  0.2  746 CQ YT9A KN04
210808_114445    50.313 Tx FT8      0  0.0 1705 YT9A GM4FVM IO85
210808_114500    50.313 Rx FT8     -6  0.2  747 GM4FVM YT9A -12
210808_114516    50.313 Tx FT8      0  0.0 1705 YT9A GM4FVM R-06
210808_114530    50.313 Rx FT8     -4  0.2  747 GM4FVM YT9A RR73
210808_114545    50.313 Tx FT8      0  0.0 1705 YT9A GM4FVM 73

I also found time this month to work a few more stations before the Es season ends.

I managed two more in the USA on 6m (AA4DD and KK4DX). Also I stumbled across an opening into the Caribbean, and worked a new country in the shape of P41E in Aruba. HC1BI was a doubtful one, and no confirmation from Ecuador suggests that this one got away.

After a suggestion from Mike GM3PPE I signed up for Log Book of the World. I had chosen not to do this when I started using eQSL about 10 years ago. Back then I was still using a paper log book. Now as I use the excellent VQLog, I can upload to both eQSL and LoTW at the touch of a button. VQLog will also download QSL indicators from both sources, meaning that I know when a QSO has been confirmed. VQLog also uploads to ClubLog.

My first download of confirmations at LoTW was for 3300 records which had been waiting for me. I uploaded everything back for about 5 years. I may do the rest later.

Despite my hopes, HC1BI was not confirmed by LoTW.

Ah well, Ecuador is still waiting for later.

Reports on the stomach pain front have declined by 35dB. They are still not yet below the noise floor.




Saturday, 17 July 2021

The drama of 144MHz Sporadic E, and how I nearly gave it all up.

Here's the thing about 2m Sporadic E ("Es"), it is very dramatic.

I was sitting here on Sunday 11 July 2021 at 15:59, musing over my previous successes and failures during previous attempts to work 2m Es. I was ready for an opening, but so far it had not happened.

For some time I have been learning how to apply my hardware set-up to try to be prepared for 2m Es openings. For instance, on 8 July I had been ready and I worked  IK8BIZ, IK6DTB, EA2Z, EA5TT, IU4CHE, IZ7UMS, IZ7UMS, IZ8OFO and IK0IXO in an hour long whirlwind of 144MHz Es. Key to this was that I was forewarned by activity on 70MHz.

That was common enough for me not to mention it on this blog at the time.

Just to put some context round this, my time trying for 2m Es from here had a very poor start. On 10 June 2011 I worked EU7AA on 2m, a distance of 2070km, and my only 2m contact of the day. It came as a complete surprise at the time. Of course I knew it was 2m Es because I had knowledge of 2m Es from before we moved here, but I was still in the dark about how to manage that aspect of VHF propagation. Looking back at the log, I had worked two stations in Estonia minutes before on 70MHz. If that was today I would have been watching 2m and be ready to pounce.

At the time I looked at "Make More Miles on VHF" and that site, which was focused on 2m Es, suggested that I might find three or four 2m events in a year, and those were almost entirely located in the Mediterranean or over the Alps. None of them came anywhere near Scotland. This seemed to me like an unpredictable means of propagation now that I had relocated north to GM-land. I decided not to go looking for 2m Es, and indeed I thought very hard about giving up on 144MHz entirely.

After that I did not work any 2m Es for four years, until three Italian stations popped up in June 2015. Those were the only Es contacts that year too. Make More Miles appeared to be correct - 2m Es was something that was welcome but not predictable enough to spend time looking for.

So what I was sitting here mulling over was - what has changed now that I think I can rely on finding multiple openings each year? I pulled out some facts. Up to that point in July 2021, the years so far has produced 55 2m Es contacts into 11 countries and 35 squares, with a best DX being IT9GSF at 2333km. 

2011, one QSO, 

2012 zero, 

2013, zero, 

2014 zero, 

2015 three, 

.... (must work these ones out)

2020 22, 

2021 so far, 55 (make that 77 by the end of the day, see later)

Then, to interrupt my pondering, up popped S58P to start a 90 minute 2m QSO-fest.

144MHz contacts (all over 1050km) at GM4FVM on 11 July 2021

22 QSOs in 8 countries. Dramatic or what?

If I include two tropo QSOs with GM and G, that brings me to 10 countries worked in just over an hour. Unlike 2011 I was prepared for this to happen and I reacted quickly.

DX Maps looked like a bad nosebleed (I have been having a few of those lately), so many stations were in the mix ...

144MHz on a 15 minute slice on DX Maps on 11 July 2021

And just to backtrack, I was interrupted by this opening. I had been musing on how much more common this has become. Basically I was analysing while I was waiting for it to open, when it opened.

Returning to my earlier thinking that day, I had done this map before the opening started.

144MHz Es contacts at GM4FVM 1 January to 10 July 2021

Not a bad map and it excludes the contacts in the first map above.

So has 2m Es got easier since 2011?

I know that I have mused about this before.

The subject came up in an email conversation with Andrew, G0JCC, and I suggested that FT8 is a big factor. He raised several things which affect 2m performance as well. These included better radios and better antennas. Also more information like DXMaps and alert emails. Certainly we did not have those before. He is correct.

Another key factor Andrew reckons are better receivers. He and I both have mast head preamps. Although their influence may be smaller on 2m than on 70cms or 23cms, they still help a lot. Correct again.

Everybody's setup will be different and will be affected by these many of these factors to a greater or lesser degree. In my case things that go with the grain here are using FT8 and more use of the lower VHF bands.

I doubt if FT8 really makes much difference in terms of distance reached, but getting us all listening on and calling on the same frequency has made a huge difference for me. And so has much more activity on 6m and 4m which makes predicting 2m Es so much simpler.

Since speaking to Andrew I have signed up for a 2m Es alert. I did it at www.gooddx.net who also do my 4m alerts. I was stuck in the past thinking that 2m Es was not for me.

Back in 2014, with no 2m Es worked since 2011, I almost gave up on 2m entirely.

Now in 2021, my analysis of previous successes on 2m Es this year was interrupted by another big 2m Es opening.

And during the opening on 11 July, I was called by Thomas SV8PEX. That would be a new country, and Thomas is 2406km from me, so a contact would also be a personal best on 2m Es. Of course I called him many times. We did not complete a QSO.

210711_161600   144.174 Rx FT8    -20  0.8 1752 GM4FVM SV8PEX JM99
210711_161618   144.174 Tx FT8      0  0.0 1750 SV8PEX GM4FVM -20

Later Thomas emailed me. He is as keen to work me as I am to work him. He confirmed what I had thought, that there was a large tropo duct in the Adriatic Sea, and that must have connected to the Es event. He said that he was hearing me for a long time, but he could not get through the pileup (!!!).

Maybe another duct, at either end, may make this possible eventually. My best 2m Es DX is still 2333km so it is not totally inconceivable. However, earlier in July I had emailed G0JCC with my view that working SV from here was "not practical". Clearly, once again, I don't know what I am talking about. Or maybe all those factors have changed my mind.

Still, SV8PEX heard me, and I heard him. That is good, but not a QSO. Next time, maybe.

I think that 2m Es is easier than it was, thanks to all these factors. However, it is still the ionosphere which calls the shots. However good your equipment, you still need nature to co-operate.

And, of course, I have my superior intellect to help me outwit the Laws of Physics.

Plus my often mentioned modesty and humility.




Friday, 2 July 2021

Summer is here (I think), and why are my reports always worse than theirs.

Ah, Summer.  Midges, flies, wasps, ants, too hot to sleep, sweaty days, noisy neighbours at stinking barbecues, traffic jams, cafes full of day trippers, grass cutting ... don't you just love it?

No, I do love it. There is the Tour de France, Cricket, long warm evenings, and relaxing beside the radio.

I know when it is Summer because the local flocks of alpacas sit down in the field rather than eat the huge banks of grass which the warm weather produces.

The Ayton Law alpacas, a recurring topic in this blog

They have been shorn again. This seems to happen a lot but early July seems a bit late to me. I thought they only gave up their fine wool once a year, but what do I know?

I find that my knowledge of small domesticated camelid shearing is much like what I know about radio propagation. I do not really know very much. Clearly they are both complicated subjects. However, I can observe what is happening, and maybe I can learn from that experience. These things can surprise me but they are very common so I should take note.

I mean, what is unusual about alpacas? It all just happens whether I take note or not. Like radio. So take note and learn from what you cannot change.

On the other hand do I actually need to understand the processes involved? Is there not a chance of just looking and marvelling without really comprehending in detail what I observe?

Perhaps there are some things I might never understand.


Anyway, June has ended with a long-ish Es event on 2m and I managed to get into part of it. Then there was also a fairly long tropo event which I managed to participate in for most of the time.

It all brought a reasonable map for June on 2m

2m contacts at GM4FVM during June 2021.

As usual, click the image to enlarge if necessary.

The Es openings accounted for my contacts into Spain and Portugal, while the tropo explains those across the North Sea. What I missed was an opening into Central Europe. Ah well, there is always next year (maybe ....).

Basically, it is astounding. 13 countries in 44 squares in a month with no EME or meteor scatter. All Es or tropo. Remarkable. When I was G8JWG I would have doubted such a thing was possible, never mind that I would do it without trying very hard. Plus I was away for a number of days during June.

On 4m I might rue that fact that I "ONLY" worked 19 countries, down from 25 in May. (But 25 is a huge number, Jim, so it was bound to be less the following month)

These are the sorts of figures which amaze me. I know I keep banging on about my station, but it is not in the superstation category. I do not want a superstation. 7 elements on 2m where I have just over 200 watts, and about 100w on all the other bands. Antennas just sufficiently high to clear the roof tiles.

Enough already.

I had some email correspondence with GM3PPE. Mike is always interesting. He was raising the subject of antenna height gain and the possible relationship between antenna height and differential signal reports.

Spurred on by his line of thought, I did some analysis on a random (?) slice of my log book. This confirmed my feelings, which mirror Mike's, that I give better reports than I get. The section of log is posted below but you will definitely have to click that one if you want to study it (personally I wouldn't bother to study it if I was you).

Random slice from the GM4FVM's VQLog log book

It has changed slightly from when I did the calculations - one doubtful contact has since been confirmed. I disregarded the doubtful ones. "Doubtful" and "failed" contacts appear in orange, but sometimes doubtful ones get confirmed later.

And, yes, EA4T was a treble, and he called me to complete it so it is not just me who chases these things.

Anyway, when I worked it out there were 43 valid entries then and the total was 28 times I gave them higher report and 12 times they gave me higher with 3 exactly the same. So, yes, I do give better reports than I get.

That does not give the full story. I gave two of those 34dB better than they gave me. Two of them! The highest the other way was someone who gave me 15dB more than I gave him. 

I remember the few instances of big numbers in the different reports. I forget the many smaller differences. When I average the whole thing out, even with two 34dBs in there, the difference taking all 43 entries into account is 3.5dB. While the massive differences might have caught my eye, the reality is not so bad. 

My final conclusion after all this waffle is that there is evidence that I give better reports than I receive. I doubt if my antennas, or my lower power or my titchy masts, are to blame. Many stations have higher noise levels than me, some use lossy analogue audio connections, and some use a lot more power than I might expect.

Then there is rapidly changing propagation. But would it always change to benefit the other station's reports? That is a mystery just like alpacas.

Perhaps nobody knows.

Or perhaps it is just not worth finding out. 

Or maybe I am happy with the results I am getting (see map/log).

Apparently the BBC do something to inform the public about alpacas. I have been told to watch "Nuzzle and Scratch". Seemingly it is about my level, or so Mrs FVM says.

Not sure what that is but I must get on to finding out.

Or not. 

I did mention I am paranoid, didn't I?




Saturday, 19 June 2021

Mostly about antennas and masts

I have had to go away for a few days. The long waffle I was writing about conditions now seems old hat. So I will cut almost all that wonderful creative writing, and just summarise it. Most of the rest is about antennas and masts. Antennas like these ones:-

Old 23cms Wimo on the left, new Dual 36el on the right.

First the round up:-

6m... I managed to work trans-Atlantic on 6m barefoot. This surprised me but a linear was not required to work a handful of stations and indeed add a new square.

4m... I managed to work a new country to bring the total to 49. The latest one was Gibraltar. Given that Gibraltar was the pinnacle of 4m DX when I started on the band it is odd that it has taken me since 1977 to work it. Still, it is in the book at last. And an elusive square in the Balearic Islands - JM29 -  was worked today.

2m... I managed to work a new country (OE) during one of several Sporadic E openings. Not sure how OE had evaded me for so long. Once again the basis of "doing the treble" works even if I feel less moved to actually work stations on all bands. I just need to see what is coming in on 6m, wait on 4m for signal to peak about about +05dB, then go for 2m. It does not work on 6m alone, I have to move up to 4m and listen there. Today I have worked EA and DL on 2m that way, and just missed 9A.

70cms... Old news, I worked a new country in the shape of Spain. That was back in March but I have only got round to mentioning it. There were several good tropo openings in late April with some new squares on offer.

23cms... Those tropo openings allowed me to have a couple more long rag chews with OZ2ND. I continue to be astounded by what I can work on 23cms.

Secondly - moving on to antennas and masts:-

This complicated re-organisation, whereby everything ended up back more or less where it was ages ago, started with moving the 2m/70cms dual band vertical.

2m/70cm vertical at GM4FVM, back where it used to be years ago

There was nothing particularly startling about this as that mounting was the first one I used when I moved here in 2009. It was there for years. However, by putting the vertical back up in that place I was able to free up the location it used to use and that allowed me to reuse the coax route to that one for the further developments which I then made later.

This was the first use I have made of Hyperflex 7 coax. I wanted to try it for a lower specification run like this, hoping that if it worked I could use it later for other things. It certainly does work, and the M&P plugs specifically made for it are very good.

The vertical is working very well in its new/old location.

I have mentioned before that I have had problem with mains breakthrough on 70cms. This has rendered my almost new nice high powered Tajfun 1000 linear pretty well redundant. I can use 100W safely with no problems. While moon bounce on 70cms is probably terminally affected, I am doing more work on 23cms instead.

To reduce problems with the 70cms breakthrough I moved its antenna to the mast furthest away from my neighbour's house. To allow for that move I took my 4m and 6m antennas down from that CUG mast. It seemed to me that I could not get both the combined 4m/6m antenna and the 2m/70cms antennas on the one mast. I was wrong about that and I had to reverse the initial thinking and get all four bands onto the one mast.

The problem was that I would need to get four runs of coax to that mast. Previously there were only two. After making a few compromises it worked because of this:-

1) by using Hyperflex 7 (H7) for the 4m antenna it would all fit through my conduits and it is much cheaper that Hyperflex 10 (H10),

2) by moving a run of H10 from the Tennamast and putting in an N-type joint I could save the cost of another run - and an N-type joint is acceptable to me on a lower frequency so that is for 50MHz

3) by using tails of H7 instead of H10 from the 2m and 70cm preamps I can squeeze in enough space to fit both antennas onto the existing stub mast (making the stub mast longer would cause neighbour problems). H7 has a much tighter minimum radius and this made the whole thing possible.

Trying the H7 on the vertical proved I could use it on 4m, and it is a lot cheaper. It is much easier to fit through the conduits in and out of the house. This may open the door to squeezing more runs through in future, though I expect 70MHz is my H7 limit for dx-type antennas. It is fine for the vertical too.

The result looks better to me than what I had before. Previously, as I was using coax with a longer minimum radius I felt that I had to take the coax down vertically from the antenna. This is because the Dual antennas have N-type sockets mounted below the boom, and it was really difficult to bend the coax back towards the boom. Such a problem does not arise with the thinner coax, so I could loop the coax round and run the leads along the boom rather as you might in a conventional single band antenna. Looking at the Dual website revealed that others have done the same.

Dual 2m/70cms yagi about the Dual 4m/6m yagi, with the CUG mast lowered

This gives me 4 elements on 6m, 5 on 4m, 7 on 2m and 12 on 70cm. Boom length is around 3m in total but used length is slightly shorter on 4m and 70cms.

Moving the vertical freed up the Ecoflex coax which fed that antenna in its previous location. The Ecoflex is now eight years old, and it is stiff and rigid. Ecoflex has been a disappointment to me, as it is inclined to form kinks and get stuck in places. When it came on the market it was the best coax I could use. Now I would not use it again.

Then it was time to put up my 36 element Dual yagi for 23cms. This goes up on the Tennamast and is double the length of the previous Wimo. The plan was to get a 10m dipole up there too but a snag developed and I have since taken it down again. For now 23cms is the only band on that mast.

36 element Dual 23cms yagi on the lowered Tennamast

I have to accept that this is the best combination of antenna locations that I can do at the moment. Given that I work five bands, having four on one mast and one on the other is not ideal. I have to point all four of the lower band yagis in the same direction, which rarely happened when I could do it differently. The two double band yagis are mounted on the weaker of the two masts, and they are all turned by the weaker of the two rotators. At least 23 cms has the more accurate rotator, which is useful for such a long antenna.  

I am working on all five bands again. I have antennas that many amateurs would think are pretty good. So I should be happy. 

I have been wondering whether a dish would be better for 23 cms but where would I mount it? I did see this idea while I was away recently.

Tree mounted dish seen at Grantown on Spey

All I would need to do would be to chop the top off one of Mrs FVM's trees.

I read that Blogger is going to stop email notifications for new blog postings from next month. That would be a problem for me. We need to see how that pans out.




Thursday, 27 May 2021

25 May 2021 - more Es, only better still

When I was attending the City of Belfast YMCA Radio Club, back in the early 1970s, learning my trade, there were some things I picked up from the old codgers with 2-letter calls who taught me what I needed to know. Everything was available on SSB with the KW-2000 and the magical new band of 15 metres. Actually, SSB and 15 metres had been around for a while, but it was amazing to them at the time.

But principally, in relation to my plan to earn a VHF licence I learned:-

1) VHF is a waste of time

2) The 2 meter band is not worth spending money on because there is no DX

3) The 4 metre band is even worse than 2m, but there is no money to spend there as everybody knows it is useless

4) This "Short Skip" thing gets in the way of DX working every year and only extends to France anyway.

This information rather flew in the face of scientific evidence, gathered during the World Geophysical Year in 1957/8 which showed the relationship between the E layer of the ionosphere, solar activity, and Sporadic E. This was what they called nuisance "Short Skip" down at the YMCA radio club.

I knew that I should listen to my "elders and betters", but I pretty soon came to realise that they were wrong in this case.

25 May followed the usual warning on Solarham. On 23 May a "minor to moderate" storm watch was put in place for 25 May. This followed a coronal mass ejection which only hit the Earth a glancing blow. As it turned out only the minor G1 level storm resulted, but that was enough for me.

23 May 2021 warning on Solarham

The result of this was a K number of 5 on 25 May and a very nice Sporadic E opening on 2 and 4 metres. Well, 6 metres too but I was not much involved in that one. 

Amongst other things, on 6m I worked UN3M in Kazakhstan at 22:41 local which rather gives a lie to the theory of Es as a daytime event but 6m is not what I am writing about today. I am not sure what the time difference to Kazakhstan is, but that was not a day time path. 

Enough about 6m.

Starting on 4 metres, at 06:43 I had a QSO with 9K2YM. I have been hoping to work Kuwait on 4m for some years and when it came I only received a -21dB report, but that will do nicely. I heard him working several G-stations but he was only workable here for a few minutes. Needless to say LL48 is a new square for me. It is definitely a best DX for me on 4m at 4974km.

Stations worked on 4m at GM4FVM on 25 May 2021

As usual, click to enlarge the images if necessary.

This was followed by a prolonged opening into the Balkan region. Over the next four hours I worked another 12 stations in seven more countries. Of the 10 additional squares, four were new.

On 2 metres the action did not start until 10:57. I had spent the previous 20 minutes calling several stations until eventually I managed to work YU7ON. Serbia is new country for me on 2m. In a little under an hour I had worked into 4 different countries.

Stations worked on 2m at GM4FVM on 25 May 2021

This proved that I was wrong two postings ago to say that my best Es DX on 2m was into Southern Spain. On 25 May I worked IT9GSF, who I had worked before. The distance then was 2333km. That must surely be my best DX on 2m Sporadic E. I was also heard on one of the small islands between Sicily and Tunisia but sadly no contact resulted. 

I had also worked YO7FWS before, but both his and IT9GSF's QSOs had been during late June. I was surprised to be doing this in May.

I will skip the map showing 2m stations worked in May to date. That included  42 QSOs to 10 countries. Interesting though that is, the 4m map is more surprising to me.

4m stations worked at GM4FVM, 1 to 26 May 2021

26 countries, 68 squares, 3 continents (Europe, Africa and Asia) in 104 QSOs. On the 4 metre band. In May. Back learning at the YMCA club I would have thought it unimaginable that this would be possible. I would have thought that because I was told that it was impossible. Back then it was the accepted truth that 4m was hardly worth the £10 it cost to buy my AM Pye Cambridge.

I have not done anything special here. I do not use any remarkable gear or even any of my many Super Powers. The special trick was done by the ionosphere. It has proved the doubters wrong. My only contribution was to ignore bogus "Sporadic E predictor" apps and stick by the basics of solar observation. I knew when to look. Joe Taylor and his WSJT-X suite has brought everybody into the same frame of mind and onto the same frequencies. It all helps, but the Sun rules the roost..

Wait, this only covers up to 26 May. Five more days to go! The possibilities are endless and we have not got to the happy times of late June or early July yet. 

I think it is all over for this month but Solarham is suggesting more possibilities for later on 27 May. My own feeling is that the glancing nature of the last CME suggests that we have had all we will get for now, but that is not clear. Predicting both the direction and magnetic polarity of such events remains uncertain.

We shall see.

Actually that is the best bit of it. 

We shall see.

What chance tropo on 2m to fill up the log? It is looking a bit empty.