RSGB
October 27, 2017
Last week was once again a mixed
bag, with good HF openings at times, and depressed maximum usable frequencies
(MUF) at others. Quieter geomagnetic conditions on Sunday and Monday saw good
openings up to and including 28MHz. But the arrival of solar material from a
coronal hole on Tuesday saw much more unsettled conditions. An initial
pre-auroral enhancement saw the good HF openings continue, but then there was
bit of a roller coaster as the MUF rose and dropped as the K-index fluctuated.
In amongst this there was DX to be had with HK3C in Columbia and HP3SS in Panama
romping in on 10 metres.
The daytime critical frequency was
often above 7MHz, giving good inter-G contacts on 40 metres, although it often
dropped back down, leaving the band only open to Europe.
Next week it currently looks like
the Sun is going to be more settled with no sign of coronal hole activity, at
least in the first half of the week. There are currently two small sunspots
visible on the solar surface and the prediction is the solar flux index will be
in the high 70s or low to mid-80s.
If our prediction about the
coronal holes is correct there should be settled HF ionospheric conditions for
most of the week, with maximum usable frequencies at their seasonal norms. This
means we could see openings up to and including 28MHz, although 14-24MHz may be
more reliable. The lower bands should also offer some good DX with 40m and 80m
coming into their own after dark. Hopefully this will be good news for the CQ
World Wide SSB contest, which takes place this weekend, the 28th and 29th.
VHF and up:
Moving into November often brings
some settled high pressure weather and this year is no exception. There is
likely to be a high pressure focus over southern UK from time to time for much
of the week. So this is a good week to check your VHF station out and try some
of those tropo paths, especially south towards the continent and across Biscay
towards Spain, the Azores and Canaries.
There will be periods when the
weather turns more unsettled with a cooler northerly, especially down the North
Sea. Showers at this time of the year can be quite active as a cold northerly
air flow crosses the relatively warm water of the North Sea, so raising the
possibility of rain scatter on the GHz bands.
Moon declination goes positive
again on Thursday and it is moving towards perigee a week today. Path losses
will fall throughout the week so it’s time to start your EME activities again
for another cycle.
Last week saw a few 50MHz sporadic
E reports, so don’t give up completely on that mode, especially as we now have
low-signal digital modes in our VHF DX tool bag.
There are no significant meteor
showers this week, so focus on the early mornings around dawn for the best
chance of QSOs via random meteor scatter.
