This is further to my last posting on this subject which you can find here or here:-
https://gm4fvm.blogspot.com/2023/06/ionoscatter-opening-on-144mhz.html
I got this screen grab of a similar opening a few days later
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| 144MHz Ionoscatter traces received at GM4FVM on 29 June 2023 |
The appearance of these traces certainly made me think that this was another Ionoscatter opening. I heard several stations and I worked SM5EPO (JP80) and SM5CUI (JO89). I have worked SM5EPO a few times - 41 contacts in the past decade on 50MHz ranging from PSK, JT65, JT6M, MSK144, and SSB (!) to FT8 but this is only the second time I have worked him on 144MHz and the first on Ionoscatter.
A few points struck me:-
1) for the third time in a row the opening was mainly towards Sweden and Finland
2) there was no Es or Iono opening at the time on 70MHz, and nothing significant on 50MHz. Can it be true that 144MHz Ionoscatter is a different from that on the lower bands? Or, more likely, perhaps the angles are just different.
3) the opening lasted for over an hour starting with my first decode at 14:02 and ending at 15:04, but undecoded traces continued until after 15:30. Stations further south seemed to do better at the start but I did not come into the shack until 14:30 so perhaps I was not beaming correctly at first.
All of this makes me think that this was definitely Ionoscatter, and most others thought the same.
I have been wondering how I have missed this propagation mode for so long (erm, 48 years ...). Maybe because I did not have enough gain in my antennas, so perhaps it was worth spending the money recently for the mild upgrade.
73 Jim
GM4FVM
I'm sure this is PMSE ionoscatter. Ice dust clouds in the D-Layer at about 85km. Research suggests we may be seeing climate change in action here, it is anticipated that there will be increasing Noctilucent Clouds, and that they will appear at lower latitudes than normal as the heat is trapped below and the ionospere cools as a result, already by 2 degrees. I look for ionoscatter on 2m regularly and 2023 has been quite extraordinary.
ReplyDeleteTim. Thanks again. I saw you in the 11 July opening too. I really enjoy seeing Noctilucent Clouds but it is scary to associate an increased incidence with climate change. Now that I know when and where to look I can see weak Iono traces quite often. However in the few papers I have read it seems that I should expect to see more on 4m and 6m. I suspect that there it is easily confused with Es. On 2m it has stood out this year in a remarkable way. 73 Jim
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