Last week was a mixed bag in terms of HF propagation. The solar flux index
hovered around the 80 mark and the K-index was poor at the weekend, although a
little more settled later in the week.
Last weekend saw the CW leg of CQ
Worldwide and the consensus was that conditions weren’t brilliant. We said that
20 and 15m would be the optimum HF bands with occasional 10m openings. This
turned out to be true as Roger, G3LDI proved by only working 67 stations on 10
metres in 48 hours. Roger said that they were mostly weak and watery European
contacts, despite using a three-element SteppIR. The days of extensive DX
openings on 10m may, alas, be behind us for a few years.
Back to the Sun,
there have been three visible sunspot groups, with region 2615 generating
M-class solar flares. So watch out for potential coronal mass ejections and
flare-induced blackouts or sudden ionospheric disturbances.
As we head
into December, now is the best time for the low bands, especially Top Band and
80m. You may find that the evening critical frequency drops so much that 40m
struggles to open to DX at times. With a typical critical frequency of around
3MHz at 2000hrs even 80m may struggle at distances less than 300-400km.
Unfortunately, geomagnetic conditions are also predicted to be unsettled from
December 7th to the 11th due to recurrent coronal hole effects.
VHF and
up propagation:
High pressure will continue to provide slightly improved
tropo conditions on the VHF/UHF bands at the beginning of the week, but there is
likely to be a slow decline later as pressure falls to the north of Britain.
Although lift conditions could affect much of the country at first, these will
become confined to the south by midweek and all gone soon after.
Don’t
forget to try the multimode part of the bands with CW or SSB, and do call CQ and
announce your activity in advance on email reflectors, DX chat such
as ON4KST.info and social media if the bands seem quiet.
The Moon is at
lowest declination today and path losses are still high, but declination goes
positive late on Thursday 8th and losses are lower. Look out for GHz bands EME
operation from Jericho from that day until 13 December by E44QX and
E44HP.
The big Geminids meteor shower is
now only a week away. The zenithal hourly rate for this shower is up to 120
meteors per hour, so it’s a really good one. We’ll have more information next
week as to the best times to operate. Look at dl1dbc.net for Virgo, a Java
real-time meteor tracking web page that may help you. Unfortunately it doesn’t
run on all browsers: you may have to try more than one before you get it to
work.
