IBP propagation predictions for the UK for May 2018

Propagation predictions for the International Beacon Chain
for the UK, May 2018.

In an effort to try to make HF propagation predictions more accurate I have been playing with a different method of producing them using the ITURHFPROP software.

Previously I had been calculating the field strength of each beacon and then converting that to an S point level. It was pointed out that this isn't the best way and that calculating the signal strength in dBm and then converting it would be better.

They are based on 100W to a dipole at 10m - we know that the IBP chain use a Cushcraft R5 antenna.

I then hit the problem as to what antenna gain do you use. This may sound simplistic, but in fact it isn't as the actual gain off a dipole will depend upon its height, its orientation and the required take-off angle.

Now, the take-off angle will depend upon what ionospheric mode is dominant at that point in time. That is, is it one F-layer hop, two F-layer hops or a combination of E and F-layer hops.

After a lot of thought and discussion I settled on setting the gain at both ends at 0dBi, which appears to give reasonable results - setting it at 2.15dBi gave over-optimistic results

Anyway, attached is the plot of predictions for the beacon chain for May 2018. I'll check to see how accurate it is and adjust the input files accordingly. The ultimate goal is to the transfer these settings to other HF predictions.

If anyone wants to report on whether they find these accurate or not please let me know. They are median predictions, which means some days may be better, some days worse.

Just click on the chart to enlarge it.

International Marconi Day 2018 from Caister Lifeboat

Chris G0DWV on the mic. with Roger G3LDI looking on.

Norfolk Amateur Radio Club managed to contact 116 other radio amateurs in 23 different countries on Saturday 22nd April 2018 when we took part in the annual International Marconi Day (IMD) event to mark the inventor's birthday.

This was the ninth year we've taken part.

Using the call GB0CMS and a mixture of Morse code, telephony (speech) and data (FT8), contacts were made with other radio amateurs across the UK, Europe, and the USA.

Notable contacts were made with other IMD stations in Italy, Ireland, Weston-Super-Mare and Poldhu, Cornwall – home of the Marconi Centre from where the inventor made the first transatlantic transmission in 1901.

We ran the all-day special event station at Caister Lifeboat to commemorate the village's original Marconi Wireless Station, which was established at Caister in 1900. The station was in a house in the High Street known as Pretoria Villa and its original purpose was to communicate with ships in the North Sea and the Cross Sands lightship.

Conditions weren’t brilliant due to a major solar disturbance (effects of a coronal hole), but we were still able to cross the Atlantic on three occasions.

We were picked up in Pennsylvania, US via FT8 at -20dB on the reverse beacon network, but didn't make any transatlantic FT8 QSOs.

The equipment used was 100W maximum from an Icom IC-7400 (20m) and an Icom IC-7300 (80/40/30m). Antennas were a W5GI dipole on 40m and my design of a monoband end-fed half-wave (EFHW) vertical for 20m. The FT8 digital mode was used for the first time to show what can be worked with just 20-25W.

We also used a Flex Maestro to remotely link into Malcolm G3PDH's home station via the internet and worked back to ourselves using his special First Class Operators' Club call for April, G4FOC. The Maestro is very impressive!

Above all, it was great fun and a good social event

Commonwealth Contest 2018 and QRP

RSGB certificate for 5th place QRP section.

Update: It turns out I came 5th in the QRP section of the 2018 Commonwealth Contest. I lost two QSOs for being "not in log",  and lost 4th place by 10pts to Dave G3YMC (which is how it should be!). Great fun and I'll do it next year, probably with my Yaesu FT817 and the addition of an EFHW vertical for 20m too.

I took part in the 2018 Commonwealth Contest this weekend on HF CW. This was always going to be a casual entry as I had other things to get on with over the weekend, not least was helping tidy the house for Mothers’ Day on Sunday!

I decided to enter the QRP category with a maximum of 5W. One reason was I knew that my good friend Dave G3YMC had won the category last year with 30 QSOs. I mean, how hard can it be to beat 30 Qs with 5W? Answer: very hard apparently!

I got going with 20m and quickly worked four stations in Malta and Cyprus. I also cracked off some of the UK HQ stations on 80m for 25pts apiece.

The afternoon saw openings to Canada, which brought in a few VEs. I was also happy to work the Cayman Islands and G3TXF on Mauritius.

My multiband fan dipoles in the loft.
Only used with QRP for EMC reasons.

Ionospheric propagation conditions were lousy with no sunspots and a geomagnetic disturbance the night before.  Fifteen metres was closed so it was a 80, 40 and 20m only event.

What you quickly realise is that many stations are using the full legal limit, so might be running 400-1,000W. If they aren’t very strong they probably won’t hear your 5W QRP station - fact of life!

So there were lots of “NR?” being sent for repeats, if they came back at all.

I went to bed about 23:30hrs and set to again at 06:45hrs. At that time 20m was dead, but there were some 40m and 80m contacts to be had and I managed to get VE in the log again. I also swept up the remaining G, GD, GI, GJ, GM and GW HQ stations as these were quite easy with 5W.

The antennas were my loft-mounted fan dipoles for 40-10m, which beat the outdoor multiband 80-10m end-fed half wave and W5GI dipole on 20m - go figure. I used the EFHW or W5GI for 40m and 80m, depending on which gave the best signal.

The “nearly” category included QSOs with Singapore, Australia, Gibraltar, New Zealand and Zambia - I just wasn’t loud enough. But hey, Cayman Islands, Canada, and Mauritius on 5W will do me!

Next year if I do it again with 5W I might put up a monoband 20m EFHW and perhaps use my Yaesu FT-817 (I don’t currently have a CAT cable for it), although the IC-756 Pro3 band scope is handy and it is an excellent rig, even when backed off to 5W. Logging/keying was with N1MM+, which worked flawlessly.

All good fun and 30 Qs won’t win it ( the highest QRP entry so far is C6AKT with 92 QSOs), but my unconfirmed overall score was higher than the 2017 winner’s, so not too shabby.

The Commonwealth Contest is a great one-weekend opportunity for UK stations to work DX with no big pileups.

IBP beacon predictions for UK using ITURHFPROP

Over Christmas and the New Year I got better acquainted with the ITURHFPROP propagation prediction software.

This is the software that Gwyn G4FKH uses to produce the monthly HF predictions for RSGB’s RadCom magazine and which was produced by the ITU.

Gwyn adapted it to produce a graphical output, which can be found at www.predtest.uk

But I was intrigued to see if I could use it to produce some predictions for the worldwide International Beacon Project (IBP) chain that runs on 14, 18, 21, 24 and 28MHz. I won’t go into too many details here about the IBP network as you can find all you would want to know at http://www.ncdxf.org/beacon/

The good news is that as they all use the same power output (100W max.) and the same antenna (pretty much a unity gain or +2.15dBi antenna) it should be fairly easy to model what the expected signal strength should be here in the UK.

ITURHFPROP runs in Windows and uses an input file with all the parameters needed, such as your QTH lat. and long., the transmitter’s lat. and long., required SNR, bandwidth, smoothed sunspot number, power etc etc.

You then run it from the command line and it creates an output file.

I ended up creating input files for each of the beacons, and a spreadsheet that can take each of the output Field Strength (dB(1uV/m)) figures and convert them into S units.

I then created a batch file that runs all of the predictions for each of the beacons in one go. With an I5 processor this takes less than about 15 seconds.

The spreadsheet then formats these so that I can produce the chart you see on the page. This may sound long-winded, but it really doesn’t take long. I’m sure someone with Python programming skills could automate the whole thing, but I wanted to make sure it worked first before going any further.

The end result has proved to be quite accurate and shows that at this point in the sunspot cycle we can’t expect miracles in terms of hearing the distant beacons. While some are audible on 14 and 18MHz, generally we are not hearing much above that.

In the UK, what have been audible quite regularly this month on 14.100MHz are RR90 (Novosibirsk, Siberia), CS3B (Madeira), 4U1UN (New York) and occasionally 4X6TU (Tel Aviv).

It also shows what the effect of an elevated K index can be as this generally means the beacons are less audible (if there at all) as the MUF declines. We have been suffering from the adverse effects of coronal holes recently and that isn't going to end any time soon.

You can see the predicted MUF over different path lengths in near real-time using the graphed ionosonde data for the UK at http://www.convectiveweather.co.uk/ionosphere/graphs.php?type=live

This was produced by fellow RSGB Propagation Studies Committee member Jim G3YLA and his colleagues at Weatherquest in Norwich.

I’ve posted the predictions here to see if they are of interest to anyone. If they are I’ll update them monthly.

To view the January IBP prediction chart full size just click here.

Radio Caroline back on Medium Wave

The Orford Ness masts

If you fancy a bit of nostalgia you can now listen to Radio Caroline again on 648kHz AM on the medium wave.

The famous pirate radio station needs little introduction, but is now broadcasting legally using (ironically) the famous Orford Ness antenna system on the Suffolk cost, formerly used to transmit the BBC World Service in English around the clock on 648 kHz from September 1982 until March 2011.

The station was founded in 1964 to play pop music all day at a time where broadcasting was dominated by the BBC and pop was played for an hour a week.

Caroline was one of five stations granted a community radio licence by Ofcom and is now running 1kW, but with a really good antenna mounted right next to the sea.

The station is 59+20dB at my home QTH 10 miles south of Norwich (JO02NN) using a Perseus SDR and a homemade 1m active loop mounted in the loft. It is also easily heard with a portable radio.

Radio enthusiasts around Europe might like to listen for it.

More information:

Orford Ness transmitter:
https://en.wikipedia.org/wiki/Orfordness_transmitting_station

Radio Caroline:
http://www.radiocaroline.co.uk/

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Propagation prediction maps updated until June 2018

I have now updated my propagation maps with the latest predicted smoothed sunspot numbers for the period up until the end of June 2018.

You can access them using this link.

The sunspot numbers continue to fall as we head towards sunspot minimum sometime around 2019.

If you use the charts look for about 60-70% reliability for SSB (yellow or hotter) and perhaps 40-50% for CW or PSK (green). For FT8 you may be able to work stations where the reliability is down to 20-30% (blue).

Of course, these are a guide and if you want to try making charts for your own station I recommend the online software at either voacap.com or www.predtest.uk/

Christmas present ideas!

As Christmas is coming, I thought I would remind people that there are some great radio-related goodies for sale at CafePress.co.uk and .com.

You can choose from a number of items, including:

• Three different types of ship's radio room clock, with silent period sectors marked
• "Remember QRT SP" Merchant Navy Radio Officer merchandise
• "Keep Calm and Work Some DX" merchandise
• "Keep Calm and Work Some CW" items
• Nikola Tesla merchandise, featuring him sitting in his Colorado Springs laboratory in 1899, surrounded by electrical arcs.

You can have the last three slogans added to T-shirts, sweatshirts, mouse mats, calendar, mugs and much more.

Just go to the Radio Room!

Or there are a number of my radio-related books that make good presents , including "Radio Propagation Explained", "Antenna Modelling", "Stealth Antennas" and "Getting Started in Amateur Radio". Use the image links on the right for more information.