Propagation News – 4 February 2018

| February 2, 2018

Solar activity remained at very low levels last week, with one barely-visible sunspot group pushing the sunspot number to a maximum of 13 and the solar flux index to 69. Geomagnetic conditions were largely settled, with some coronal hole activity pushing the K-index to three at times.

Despite the low SFI, there was band activity up to at least 21MHz. Z60A in Kosovo came up to a 59 on 15 metres CW on Wednesday and the FT8 frequency, 21.074MHz, revealed varying amounts of activity. So the message is that despite a low solar flux index it does pay to check the upper bands regularly. The FT8 frequencies are a good starting point, as are the International Beacon Project frequencies.

Next week NOAA predicts the solar flux index will remain around the 70 mark. Geomagnetic conditions should be slightly unsettled, with a maximum K-index of three throughout the week, rising to four on Saturday, the 10th, due to ongoing coronal hole activity.

All eyes and ears will be on Bouvet Island this week as the 3Y0Z DXpedition gets underway. Described as the most remote island on Earth, Bouvet is 1,000 miles north of Antarctica and a near north-south 7,400km path from the UK. But it won’t be an easy one as signals are likely to be fairly weak unless you have a beam. Checking with the VOACAP online software shows 17m or 15m might offer the best chance of a daytime contact, with 17m peaking around 1600 to 1800UTC. 40m and 30m offer the best chance of an evening or night time path. By next week we should have a better idea of how strong they are.

VHF and up

This week we are in a cold northerly with heavy wintry showers around the coasts, sometimes driven a fair way inland at times. We therefore have the prospects of rain scatter on the microwave bands, and you can track the showers on one of the many weather radars out there on the web.

The pressure has remained low through this weekend, but high pressure returns early next week. It’s unlikely that this will produce good enough inversions to produce much tropo. In any event, this is soon replaced by more unsettled weather after mid-week. This will mean wet and windy weather at times and unlikely to do much for VHF/UHF conditions.

Random meteor rates are still low and there are no showers due until the Lyrids shower at the end of April. EME conditions will decline this week as Moon declination goes negative today, meaning shorter Moon windows in the Northern hemisphere. Path losses will increase all week as we approach apogee a week today. So, it’s looking like a good week to do some VHF DXing on the various artificial satellites. Look on the AMSAT-UK website for details.

Category: GB2RS Propagation News