Episode 1.1: When conditions go horribly bad

Episode 1.1: When conditions go horribly bad

 

This is a special post-contest update on April 23, 2017.

Oh my goodness, what a terrible weekend on the radio!

Feels like I wasted a couple of days there in the SP International DX teletype and the BARTG 75 RTTY contests.

Didn’t make many contacts in either one of them.

In the previous podcast I mentioned the importance of working all 6 continents. Well, I managed to end up with 3 continents in the log. I did get one European station — an EA station in Spain on 20M by pointing south of the aurora — but that was it from east of the Atlantic ocean.

I found a couple of South American stations and the rest were all North America. I did not hear any KH6 Hawaiian stations or any of the South Pacific ZL/VK stations in New Zealand or Australia, so I was shut out for 3 continents and had only 3 in the log.

It’s about the worst performance I’ve had in the SP DX RTTY contest in many years. That speaks to the conditions of the solar cycle.

We are definitely in the bottom of the trough of solar cycle 24, so that means the next year — perhaps two years — are going to be similar to what we saw this weekend.

There will be moments of happiness and smiles and sunshine, as conditions aren’t always this terrible, but we sure had a look at what the future holds for the next while.

Seeing the numbers

I thought I might give you some indication visually of what the conditions looked like over the weekend, so I went to the orcaDXCC.org website and took some snapshots of the propagation dashboard. By taking a look at the two screen shots from the morning and the afternoon of Saturday, April 23, you get a visual indication of how the solar and geomagnetic numbers changed across the day.

Propagation conditions about 10 hours later — at 0140Z on Sunday
Propagation conditions at 1520Z on Saturday

The dashboard, which has been in use since 2010 and compares favorably with real-world conditions, indicates in real-time what the band conditions should be, based on solar flux, sunspot levels, the A-index and K-index, as well as geomagnetic conditions.

At 1520 UTC on Saturday morning, April 22, we were enduring a geomagnetic storm at a minor storm level. The solar flux was 82, driven by 39 sunspots. However the K-index was 6.

Now, it’s nice when the K-index is at 1 or 2, because that means the A-index will be low.

The A-index is a cumulative number that’s based on the K-index over several hours. When the K-index is elevated the A-index will rise and it will rise dramatically if the K-index is elevated to a level like 6, as it was on Saturday.

So conditions really did get worse as the day went on. The aurora level was actually falling during the day, as you’ll see in the screenshots that I’ve included in the show notes for this special episode 1.1.

The aurora had fallen from 8.4 in the morning to 6.7 in the afternoon. That means it had fallen from about 55 gigawatts of power in the ionosphere to about 25 gigawatts of power in the ionosphere.

The big difference through morning to the afternoon – the obvious clue to why the bands got even worse as the day went on — was the soaring A-index.

Remember, the K-index in the morning was 6 and in the afternoon the K-index had fallen to 4.

Now, 4 or 6 are both high numbers for the K-index. And because of the number of hours that K had been elevated, the cumulative A-index went up – from 47 in the morning to 51 in the afternoon.

That really does mean that bands are completely wiped out.

You will get some reasonably useful conditions on short hops across the continent on 20 meters, for example, and that’s what I saw. I was hearing signals — they weren’t strong and there was some fading on the signals between me and Florida and the US southeast; however, on the lower bands conditions were quite bleak, especially as darkness fell here in western North America.

Now we look ahead to a series of QSO parties while we await CQ WPX CW in late May. That one will be a real trial of patience if this weekend’s conditions repeat a month from now.


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Thanks for taking an extra few minutes this week for the Episode 1.1 post-contest update.

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