Propagation News – 26 August 2018

This past week was characterised by low sunspot numbers and unsettled geomagnetic conditions. The K index hit three and four during the week due to yet another large elongated coronal hole on the Sun’s surface. But it wasn’t all bad news as there was DX to be had if you employed the right equipment. Roger, G3LDI reported working Hank, W6SX near the Yosemite region of California, USA, on 20 metres during a CWops contest in the early afternoon on Wednesday. Hank was using a basic wire antenna while Roger was using a SteppIR beam at height. Both were using their respective full legal power limits.

The TX5T DXpedition to the Austral Islands in the South Pacific proved to be a trickier one to work, but a number of G stations did manage to make the trip, with 40 and 80m contacts surprisingly making a showing.

Next week NOAA predicts the solar flux index will be around 66, which is about as low as it can get in any solar cycle. The better news is that there appears to be a lack of solar coronal holes for the time being, so geomagnetic conditions may be more settled, with a maximum K index of two.

Expect maximum usable frequencies to be in the 14 to 18MHz range, with the potential for occasional Sporadic-E openings on the higher bands, although we are now well past the summer peak.

It is perhaps still a little too early in the season to see the expected autumn upturn in F-layer HF conditions, but there is still DX to be had if you search for it. This may be a good time to attend to your HF antennas before the autumn, ready to make the most of potentially better DX conditions in a month or so.

It’s a much more unsettled flavour to the weather this week, with low pressure close to northern Britain. What’s left of the high pressure will have moved into the continent and retreated back to the Azores. This will probably limit the Tropo activity compared with recent events although, as often is the case, it will be mainly the south of the country that might see any temporary Tropo at times. What that leaves us with is the prospect of some occasional microwave band rain scatter in the unsettled phase of our weather.

There remains the prospect of the dying embers of this year’s Sporadic-E season. It is always worth a check on the clusters and HF/VHF bands from 10 metres up to 4 metres, but it is perhaps a bit late in the season to expect much on 2 metres. The unsettled weather will bring some jet streams into play over northwest Europe and that can be a good thing for turbulence and Sporadic-E.

Moon declination is still negative and path losses are high today, but by the time we get to next Saturday and Sunday’s EME activity from the 32-metre Dish at Goonhilly in Cornwall it will be positive and losses lower. The team plan to be active on 1st and 2nd September as GB6GHY, concentrating on 3.4GHz on the 1st and 5.7GHz on the 2nd. Look for them on the HB9Q EME logger, between about 0800 and 1200UTC, earlier if possible, and if you can elevate your dish to the Moon, take a listen. Their CW should be receivable on a 1m dish with a decent preamp.

And that’s all from the propagation team this week.

Category: GB2RS Propagation News