Sunday, 31 December 2017

FT8 and the arrival of even more Christmas Es

Happy Hogmanay Everybody.

Storm Dylan is currently whipping round and about my masts, but apparently the weather forecast is that it will indeed be braw in Edinburgh at midnight tonight, and it may even be bracing for the Loony Dook in the waters of the Firth of Forth tomorrow.

I hope to stay dry and warm here.
It was only two days ago that I commented on the Christmas Es here.

Later on 29 December produced another fine 6m opening bringing the total Es picture in the week since Christmas to this:-
Es QSOs at GM4FVM 25 to 31 December 2017
This of course excludes meteor scatter and 10m WSPR which are usually my stalwarts at this time of year, and is only up to 13:00 on the 31st. There were more stations available to work but I have to live you know! Life outside radio goes on.

What strikes me is the difference from the same period last year
Es QSOs at GM4FVM 25 to 31 December 2016
In fact, all the QSOs last year were on one day in an opening which lasted an hour.

Natural variation? Probably.

It is called Sporadic E for a reason.

However, it is worth just thinking about what has changed since last year.

All my 2017 Es QSOs were made using the FT8.  During the same period in 2016 FT8 was not available, so two were on SSB and the rest on JT65.

This year the openings have lasted 27 hours.

Could the arrival of FT8 have made a difference?

My posting on 21 September, here, sets out a possible mechanism suggesting how some data modes can transform a marginal situation into a QSO-feast. It could not open a closed band, but it could make just enough difference to achieve QSOs.

But surely I was using a data mode (JT65) in 2016? True, but not so many others were. FT8 has developed a "cult following". Also, although FT8 is theoretically less efficient that JT65, FT8 harbours a major advantage in these marginal conditions. By using FT8 you can complete a QSO between two and four times faster than on JT65. In rapidly fading periods this makes all the difference between finishing a QSO and not making it. I did not record the times in 2016 when I got only one over from the other station, but I know it happened a lot with JT65.

There is not enough evidence to draw any conclusion yet. We need many periods of observation for comparison, but there might be something in this. On the other hand, the fanatical take-up of FT8 will no doubt decline as its newness wears off.

There is no doubt either that the availability of stations at the far end of a QSO often has more influence on the QSO count than the conditions. So perhaps this is just a storm in a teacup, driven by a few articles about FT8.

On the other hand I did notice that a lot of the stations I worked were callsigns already in the log. I had worked them, usually in the Summer, in various years. In 2016 I worked them on JT9, in 2014 on JT65, in 2013 on PSK .... anyway, they were regulars and not people drawn into 6m data after a burst of publicity following the launch of FT8.

I also rather absent mindedly clipped a page out of the 6m DX-cluster for 29 December. There are 37 Es QSOs recorded in 28 minutes, 27 on FT8, 8 on CW and 2 on SSB. Is it just that FT8 is more popular, or could it (and CW of course) just be better at producing QSOs than SSB? Not enough evidence to tell yet, but I think it is worth considering.

When I started using data modes (in the 1970s) they were viewed as a (rather poor) substitute for SSB, not something measurably better. I need to recalibrate my thoughts on this.

Right I am off to browse through my log book.

Before anybody asks, here is the map for the same period 2015 when I was using JT65 and JT9 ...
Es QSOs at GM4FVM 25 to 31 December 2015

I might not get too much time to browse as there is a slight uptick in geomagnetic activity predicted for 1 January, round about the same time as the Quadrantid and Ursids meteor showers usually keep me busy.

Have a great New Year.



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