Propagation News – 24 September 2017

| September 22, 2017

Last week saw sunspot numbers decline, but geomagnetic conditions become more settled. This, plus the fact we are heading into autumn, resulted in better HF conditions, with 21MHz opening to DX for short periods. The CS3B Madeira and 4X6TU Israel beacons on 21.150MHz were both audible at times and Jim, G3YLA reports working S01WS in Western Sahara on the band.

Not to be outdone, the lower bands have also been active, with UK operators on the DXpedition to St Pierre and Miquelon being worked from the UK on 160, 80, 40 and 30 metres. The better critical frequencies and therefore higher MUFs mean 40 metres has also been open to shorter skip at times, perhaps with a minimum of about 500km.

Next week NOAA predicts the solar flux index may increase slowly up to and beyond 100 once again. However, there is a strong possibility that geomagnetic conditions may be unsettled all week due to coronal hole activity and the potential for coronal mass ejections from the active sunspots that are predicted.

Currently, VOACAP Online suggests that reasonably-equipped UK stations have around a 50 percent chance of working New York on 20 metres CW from around 1800 to 2030hrs. This should improve to about 70 percent as we head into mid-October, with 17 and 15 metres both offering better reliability too.

With the better autumnal HF conditions coming, it is worth playing with the online tools at and to get a better understanding of the best times to work various parts of the world on HF.

And now the VHF and up propagation news.

It’s been a good week for rain scatter on the GHz bands, with daily propagation over to the Netherlands and Belgium and intra-UK. Sadly this has not been matched by activity, but a few good QSOs were reported by those who were aware.

This week sees a welcome return of high pressure nearby, to the east of the UK. This will allow stations in the south and east of the country to enjoy slightly enhanced conditions. The position of the high would favour tropo paths up the east coast and across the southern North Sea. This will probably be a brief period of tropo before low pressure from the Atlantic drifts in towards the UK in the second half of the week. The high remains nearby over Scandinavia, with a ridge extending southwest across France into Spain. This may possibly offer some tropo options to the south for stations on the south coast.

There is a low rate meteor shower, the daytime Sextantids, on Wednesday, so continue to look before dawn for the best random meteor scatter contacts.

The Moon is at maximum negative declination and apogee on Wednesday so losses are at their greatest and Moon windows short. So this is a good week to catch up on antenna maintenance for the autumn.

Category: GB2RS Propagation News