October 30, 2015
It has been another week with great HF conditions. Last weekend gave many people the chance to work DX on 10 metres in the CQ Worldwide contest.
The solar flux index stayed above 110 and geomagnetic conditions were generally quiet, especially compared with the problems we had with high speed solar wind streams last month. This, coupled with better general autumnal propagation, meant the maximum useable frequency headed past 29MHz. Many low-powered 10 metre beacons in the US could be heard in the UK, which is always a good sign. However, there was also a proton event on Thursday that may have affected polar paths.
Propagation on 10 metres to the United States, Caribbean and South America has improved dramatically, so make the most of it while it lasts.
Next week NOAA predicts the solar flux index will decline, possibly into the mid-eighties. The K-index is predicted to rise to five or six on Tuesday or Wednesday due to incoming plasma from the sun. If the prediction is correct, expect MUFs to drop and HF conditions to be poorer mid week.
As we are now in November, according to VOACAP you should be using a smoothed sunspot number of 46.4 for your propagation prediction programs.
VHF and up propagation news:
The first week of November looks like getting off to an unsettled start on Sunday in the far north and west, but with some promising lift conditions in the south-east of the country.
This could be the start of a good week for VHF/UHF/microwave ducting with high pressure residing over the continent for much of the time, and allowing substantial parts of the UK to couple into the action. Even the north should benefit from these quieter weather conditions later. The most likely extended paths will be towards the south into France as far as the Alps and Pyrenees, and eastwards across the North Sea to the Baltic. So it’s a good week for checking the multimode sections of the bands. SSB and CW should prove especially rewarding, and it is worth spending a few minutes getting a beacon list printed off.
If you are new to these higher frequencies, remember that cross polarisation is not a good philosophy for VHF DXing. It may be time to experiment with just a simple horizontal wire dipole, rather than struggle with a collinear.
There are no major meteor showers this week, but we have the Leonids on 17 and 18 November to look forward to.
For EME operators, next week shows falling declination and moon window length with increasing losses. There is still plenty of Moon time, with up to 15 hours of moon visibility on Monday, falling to 12 hours next Sunday where losses will be close to maximum.