Thursday, 14 September 2023

A tropo opening at last.

Perhaps the strangest thing about this latest tropo opening is that it is so long since the last one. My most recent posting here on this subject was in early June, 3 months ago.

I think of Summer in this part of the UK as not being particularly hot but often having long settled sunny spells associated with high atmospheric pressure which brings tropospheric enhancement. Not this Summer. After a promising start, July and August were grey and miserable with low pressure for weeks on end. Of course the low pressure does not last for ever, just like the high pressure never did.

During the period 4 to 9 September a series of high pressures passed from West to East. For a time there was a low pressure system to the North West of me (as there often is) which brought winds and shut down the propagation, but generally conditions remained up for most of that period.

Things seemed to be best on 144MHz, with 432 not bad and 1296 pretty poor.

144MHz contacts at GM4FVM 4to 9 September 2023

39 QSOs into 30 different squares was a very agreeable outcome.

Those of you who have clicked on the image to give a better view of the map may have noticed that F6ASP appears to have his station located in the middle of the English Channel. If that was true the UK Border Agency would be out to try to send him back to France. In fact what has happened here is that because I only have a four character locator for that station the map assumes that he is in the middle of the JO00 square. This happens a lot, and I have to look up six character locators for some stations who do not list them on, or for which VQlog does not have the full details. In this case F6ASP does not have a more precise locator anywhere that I can find it, so he will have to remain in a watery position for now. 

Queue the tune "Sailing By" written by Ronald Binge, which is played by the BBC before the Shipping Forecast. This is now used by anyone too lazy to find anything more relevant to the sea. I am as lazy as the next man. I know Claude Debussy's La Mer and Benjamin Britten's Sea Interludes might be better but perhaps I will just stick to what I always do. This "don't blame the lazy" theme will return at the end of this posting, but by then it might have some amateur radio relevance [about time Jim, this is not a music blog].

On 5 September I had the chance to operate for a short period during the NAC contest. I switched to using the EU contest mode in WSJT-X and worked SM7VUK, DG1BHA, SB7A, SK7OL and SM7SPG in 33 minutes. I could have worked more but had to go to attend to domestic duties. Contests have their uses but I am not about to become a slave to them.

Things seemed to be going pretty well on 5 September so I decided to try coming on to 2m at 05:00 local time on 6 September. This was to see if the supposed good conditions early in the day would pan out. I was pretty pleased then to work EU3AI in KO22, a distance of 1757km, at 05:40 UTC. Of course I have worked him before (!), but this time it was tropo which is definitely the hardest way to work Belarus. 

Having worked Belarus on 2m both of the easy ways, by meteor scatter and Sporadic E, doing it on tropo seemed to complete the set somehow. Just as people say that if the Jumbo Visma cycling team win the Vuelta a EspaƱa this week, resulting in a clean sweep of winning all three Grand tours this year, somehow doing it three times in different circumstances makes them invincible. It doesn't mean that of course, and nor does me working Belarus three different ways mean anything very significant other than that I was in the right place three times over.

Still, I am claiming that my early arrival on the band that morning was the result of superior planning on my part and shows how knowledgeable, dedicated and devoted I am to my hobby. It doesn't mean that of course. Ever heard on insomnia? What else do you do at that time of the morning other than listen to the radio?

I also heard two Russian stations in the Saint Petersburg region and one Ukrainian station, but did not work any of those. I cannot complain though as 15 countries worked on 2m is five days is still pretty good.

OH1ND in KP00 is 1493km, still a good trip on 2m, and LY2WR in KO24 is 1681km, barely 70km short of EU3AI. So there was plenty of action short of the ODX.

Moving on to 70cm

432MHz contacts at GM4FVM 4 to 9 September 2023

35 QSOs on 70cm is only four less than the 2m total and shows how well we can do on that band during reasonable lift in conditions. SM0DJW in JO88 is a pretty good contact on this band at 1242km. There were more contacts into PA on 70cm and there is no doubt that the path from me into Benelux on 70cm can often be better than 2m. Once again the DXCC total is pretty good - nine countries worked on 70cm would have been a good lifetime haul for me when I started out on this band. 

Meanwhile on 23cm...

1296MHz contacts at GM4FVM 4 to 9 September 2023

On the face of it, 23cm looks like a bit of a washout compared with the other bands. It did not feel like that at all. The QSO with  G4YTL was particularly interesting. We were in contact via KST chat and after setting up the initial details, it took 20 transmissions from me on FT8 for David to decode the two that he needed to complete the contact. That is over a distance of just 427km during elevated conditions. We then switched to Q65 and competed a second QSO in just over a minute. In FT8 David could not decode 18 of my 20 transmissions, while on Q65 he decoded all of them (just three needed to complete).

There is nothing very starling about this. I have worked David on Q65 on 23cm before. What surprised me was seeing the comparison in modes play out. Q65 is simply a superior mode to FT8. The difference may not matter much on HF or during favourable conditions on other bands. However, once we reach marginal conditions or bring into play scatter propagation as with aircraft scatter or EME, then Q65 shows how good it always has been.

This brings me back to the question I often ask myself. Why, when Q65 is better, do VHF and above operators still not use it? It seems to me to be absurd that many EME operators on 2m still use JT65. If we could bring Q65 to bear during ionoscatter or troposcatter it might well make the difference between completing a contact and failing totally.

Sure, if you are on a chat room like KST (argh, how I dislike that but needs must) you can set up a Q65 contact. But what about the generality of contacts which happen randomly? Could VHF operators not decide as a group to use Q65 instead of FT8? This is a bit like asking why some people still use FSK441 or RTTY. They use outdated protocols because they do not want to change. They have every right to use old modes, and I do not deny them that right. But that is like saying that they have the right to miss all the QSOs. Sure they do. Knock yourself out with that idea, mate.

In conclusion ... this opening was a test for me to check out the two band with two feeds DUAL 2m/70cm antenna. I doubt that it can be quite as good as the I0JXX for 2m and the Wimo for 70cm because they are single band antennas and are designed for that one job. However, it went pretty well and I think I should be content enough about that.

Now, the 23cm antenna might now come into the reckoning for change in some way. Elevation? Time to think again about 23cm EME?



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