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Tuesday, November 7, 2023

Skewed path on the 24 MHz band between Europe and the Pacific - Nov 2023


I found this item in the most recent GB2RB news bulletin from the RSGB of interest... "Phil, GU0SUP reports working Jan, E51JAN on the North Cook Islands on 12m FT8 Fox and Hound mode at around 1630UTC. He said that, as it was almost dark, he didn't expect to hear anything, but had a good copy on him at 190 degrees, so gave him a call. He came straight back.

Phil said that this was a big surprise, and he is not sure how it worked. It was quite a skewed path, with pretty much no copy on the real headings, short or long path."

The map above roughly shows the various paths for this 24 MHz (12m) band contact. From GU0SUP's location on the island of Guernsey, the short path goes up over Greenland. The long path would go in the opposite direction (148 deg) and down over Africa.

The reported path of 190 degrees takes the signal down into the Atlantic region between South America and Africa.

Commentary... The QRZ page for GU0SUP says that he is using a TGM Communications MQ26 mini-beam which would have a very broad beamwidth. We can't know for certain if the actual path was 190 deg or not. 

All we can take from the report is that it wasn't short path or long path but was skewed in roughly a south-westerly direction.


The image above is one I made before for an opening on the 50 MHz band between Europe and the South Pacific with a skewed path. Post HERE

This most recent report for the 24 MHz may well be the same? Did the signals get trapped in the Trans-Equatorial Propagation (TEP) region and allow the skewed path westwards from Europe to the Pacific?

Skewed paths should be even more common and pronounced at a lower frequency like 24 MHz as compared to 50 MHz.

I suspect that the TEP region has a huge impact on signals that most of us don't appreciate. On the HF bands, so many people are using omni-directional antennas or beams with a very low beamwidth that skewed paths are not obvious unless they are at almost right angles to the short and long paths.

Food for thought... How many people on the HF bands are looking for DX-peditions or DX stations on the textbook short or long paths when they should be thinking outside the box and looking for skewed paths?

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