Monday, 24 April 2017

A portable multi-band End-Fed Half Wave (EFHW) antenna for 40-10m

The camping washing line spool used for the antenna wire.
A few people have asked about the 30m antenna Norfolk Amateur Radio Club used for its International Marconi Day (IMD) operations at Caister Lifeboat this year.

Ten Megahertz (30m) turned out to be a useful band for us, allowing CW contact after CW contact, despite poor conditions after a geomagnetic storm and a K index of five.

The antenna we used was a portable 40-10m multi-band end-fed half wave (EFHW) with a 49:1 Unun using an FT240-43 toroid.

It used a wire 9m vertically metres up a fishing pole and then about 5.8m out.

The novel thing was that I only built it the day before and it uses a Coghlan camping washing line spool with the string taken off and about 21m of wire wound onto it.

Caister Marconi radio station makes nearly 200 contacts

Right: Rodney G0CBO and Kim G4WUG contact another other 
radio amateur with Morse code from GB0CMS at 
Caister Lifeboat on International Marconi Day.

Members of the Norfolk Amateur Radio Club (NARC) managed to contact 193 other radio amateurs in 31 different countries on Saturday 22nd April 2017 when they took part in the annual International Marconi Day at the Caister Lifeboat Visitor Centre to mark the inventor's birthday.

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

Notable contacts were with other special Marconi stations in the UK, Italy, and Ireland.

NARC 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.

On Saturday, the closest to Guglielmo Marconi's birthday, stations around the world are set up at sites with historical links to the inventor's work. These include Poldhu in England; Cape Cod Massachusetts; Glace Bay, Nova Scotia; Villa Griffone, Bologna, Italy and many others.

Visitors to the station including many other local radio amateurs and members of the public.

Steve G0KYA, who organised the event, said: “Conditions weren’t brilliant due to the effects of a solar coronal hole, but we started off by talking to Ian VK3MO, an amateur near Melbourne, Australia on SSB.

“We then went on to make contacts with other radio enthusiasts all over Europe and as far as North Carolina, USA using speech, PSK and Morse code.

“New this year was CW operation on 30m, which proved very effective with long runs into Europe using a new prototype end fed half wave antenna (EFHW). We also had the club IC-7300 running on 40m, which worked well but highlighted a few things we need to check, such as the overload light flashing when the other station was on 30m and we tried to work on 20m.”

“My thanks to everyone who helped on the day and to to Caister Lifeboat for letting us set up the station.”

The equipment used was 100W from an Icom IC-756 Pro3 (30/20m) and Icom IC-7300 (40m). Antennas were a W5GI dipole on 40m and G0KYA's monoband end-fed half-wave verticals for HF.

Thursday, 6 April 2017

International Marconi Day, April 22 2017

Saturday 22nd April 2017 is International Marconi Day when stations around the world celebrate the birthday of Guglielmo Marconi.

It is also a good opportunity for you to gain a very nice certificate. All you have to do is work 15 award stations and send in a log extract - you don't need QSL cards.

I shall be helping to run GB0CMS again this year at Caister Lifeboat in Norfolk, UK.

There is short video that looks at the equipment the club used to make 165 contacts in 24 countries on Saturday 30 April 2011. And another for the 2012 event when we made more than 500 contacts.

See and

To help UK stations work the requisite number of IMD stations I have prepared some HF propagation predictions. You can view these online.

You can find out more about IMD at:

Wednesday, 29 March 2017

You never know who you might hear on HF!

Colonel Doug Wheelock, KF5BOC
I was tuning around HF today and heard an American accent on 14.275MHz. This was odd as conditions had been really bad because of a geomagnetic storm, complete with a K index of six.

I didn't think there would be much propagation to the US.

Listening carefully it turned out to be Keith RA/WD9GET in Star City, Russia. Keith is a flight surgeon with NASA and was operating the amateur radio station at the cosmonaut/astronaut training centre in Russia.

Before I had a chance to call him he said he was taking a break. That was a shame, but I left the rig running on 14.275.

Ten minutes later RA/KF5BOC came up on the frequency and was calling, so I replied. He was a good 59 on my 40-10m EFHW antenna at about 25feet.

It turned out to be Colonel Doug Wheelock KF5BOC, the International Space Station commander, who is in Russia at the Gagarin Space Centre to help with training. Blow me down!

So Doug and I were able to have a quick chat and I mentioned how I had been involved in the ISS schools contact with UK ESA astronaut Tim Peake. When we finished the pile-up started - big time!

Just shows you never know what you going to come across on HF.

Friday, 27 January 2017

A shortened multi-band End-Fed Half Wave (EFHW) antenna for 80-10m

The 80-10m EFHW
This is a shortened multiband antenna, about 23m long, for 80m-10m that offers low SWR (1.3:1) on 80m and 40m, and below 3:1 on 20, 15 and 10m. The antenna has almost 300kHz bandwidth on 80m between 3:1 SWR points. But performance is down about 8-12db on a dipole on 80m.

This design came from attempts to find an 80m antenna that could fit into a small space. This was because Norfolk Amateur Radio Club likes to take part in the 80m Club Championship (we won in 2016), but many members don't have enough space for a full size (132ft) dipole or the 100-102 feet needed for a G5RV or W5GI antenna.

This antenna lets you get on to 80m in a horizontal distance of about 12m (40ft) when used as an inverted sloper with the apex at 8m, although you'll be down a couple of S points on a dipole. But if the other station is 59+20dB, you'll be about 59 +5 or 10db, so all is not lost!

I take little credit for this as it was outlined in PD7MAA's and IK0IXI's blogs after extensive work on the antenna in the Netherlands. However, there was little on their blogs in terms of its performance or SWR characteristics. Hence this write-up.

Download the 80-10m EFHW antenna guide

Update 29/1/17:
I've updated the guide to look at replacing the coil with a 7MHz trap and also putting the antenna up as an inverted V.  The trap and about 14.2m of insulated wire would improve the 80m performance a little, if you have the space, but possibly at the cost of the 14MHz performance. Surprisingly the MMANA-GAL model suggests the inverted V would be worse for 80m NVIS communication.

Update 09/02/17
I thought I would bite the bullet and took the wire and loading coil off and replaced it with about 130ft of insulated wire. This needs some final tuning, but gives a low SWR across 80 and 40m, and SWRs below 3:1 across the higher bands. The last 20-25 feet had to run along a wooden fence. Performance on 80m was equal to or down 1-2 S pts on the W5GI. Performance on 40m was down quite a bit, perhaps 2-3 S pts.

It appeared to be directional compared with the W5GI (which was at right angles). Equal performance on 20m to Tunisia.

So the performance on 80m was marginally better than the shortened version, but the 40m performance was worse. This was confirmed with WPSR tests. The performance on 20m was roughly similar. The bands higher than 20m were mostly closed during the test.

I think the compromise position of the 132ft wire didn't help the antenna's performance and I think that overall, the 66ft and loading coil version was better on 40m an higher.. If you could get the whole wire in the clear you might better results.

Monday, 9 January 2017

HF and solar conditions continue to decline

I've now updated my hourly HF propagation charts for the UK for the next three months.

The charts, with real time solar information, can be found at
You can definitely see the effects of the current poor solar conditions. As the charts are produced by VOACAP it is suggested we use the smoothed sunspot number (SSN) for the calculations.

In January 2016 the SSN was 44.8, but this month it is just 29.2. In fact, the actual daily sunspot number is even lower than this at around zero to 11 with a solar flux index in the low 70s.

Given that at sunspot minimum we wouldn't expect the solar flux index to drop below 66 you can see that we are very close to the kind of conditions we can expect over the next few years.

NASA says the current sunspot cycle is the smallest since cycle 14, which had a maximum smoothed sunspot number of 107.2 in February of 1906.

The current prediction for sunspot cycle 24 (this one) gives a smoothed sunspot number maximum of about 101 in late 2013.

The next sunspot minimum is currently predicted to occur around 2019-2020.

The solar maximum for cycle 25 is predicted to be around 2025, possibly with a monthly smoothed maximum sunspot number of around 60-65. If true, this is almost down to Dalton Minimum levels.

What we are seeing is that the ionosphere is currently struggling to regularly open up to DX at frequencies much higher than about 18MHz. Around the UK we are even finding 40m (7MHz) closing to inter-G contacts by early afternoon, if it opens at all.

This means that 80m (3.5MHz) and 60m (5MHz) are coming into their own, although both are struggling with inter-G contacts by late afternoon.

A succession of coronal holes and their associated high-speed solar wind streams are also causing disruption to the ionosphere. While these are typical of this point in the sunspot cycle they are generally not helping DX at all.

This week's high K indices have been caused by such a hole, although the solar wind has mostly had a north-facing Bz field, which is less likely to couple with the Earth's magnetic field, and we have't seen the very high K indices that indicate severe auroral conditions.

Lastly, readers might be interested in a new HF propagation tool based on the ITU's ITURHFPROP software and developed by Gwyn G4FKH. The URL is

The 'Area Coverage' predictions have been available for some time, but a new Point-to-Point prediction tool is now available. Clicking on the link starts the process, when the form is filled out a series of plots are available depicting propagation between the required Tx. and Rx. sites.

New features include various colour schemes for the plots allowing users with colour preferences to make the best viewing choice for themselves.

Steve G0KYA

Monday, 2 January 2017

Some Christmas QRP HF operating

Elecraft K1 on 40m QRP frequency.
The period from Christmas to the New Year is traditionally the time for the GQRP “ Winter Sports”.

I don't take this too seriously as there are plenty of other calls on my time, but it is an opportunity to get on the air and work a few stations with 5W CW or 10W SSB.

This year got off to a good start with a contact on 23rd December with SK6SAQ at Grimeton in Sweden – home to the Alexanderson alternator that puts out a 200kW signal on 17.2kHz.

SAQ also has a special event callsign so it was good to get operator Kjell in the log using 5W from a Yaesu FT-991 into an outside EFHW. I really must visit Grimeton one day.

I also dragged out my Bencher paddle as I was sending some awful Morse with my Kent single lever I think I was getting key bounce so will have to take a closer look. The Bencher was fine, which was good news.

After Christmas I turned to my Elecraft K1, which I finished in the summer after owning the kit for about 12 years!

This brought CW QSOs with Peter OM0WR in the Slovak Republic on 7.029MHz with 5W into my loft-mounted zig-zag dipole.

The YT160TESLA QSL card.
Then it was YT160TESLA on 20m celebrating 160 years since the birth of Nikola Tesla in Serbia. I really want their QSL card which looks great and worked them on 40m in March. As they went QRT at the end of 2016 it really was a last chance.

I have an Icom IC-7300 on test, which belongs to my local club and that brought 9A1700SBD in Dubrovnik, Croatia, although it took 25W to get through.
The view across the rooftops of Dubrovnic, Croatia.

2016 was the 1700th anniversary of St. Blaise, patron saint of Dubrovnik – if you ever get the chance to go there, do as it is absolutely beautiful.

Station LZ463PP then went in the log with 10W from the IC-7300 and a W5GI dipole on 17m SSB, so still QRP. It was celebrating 463 years of Saint Patapii.

Finally I had a nice (but weak) QSO with Ian EA7JUK in Lubrin, Spain on 20m CW using 5W from the K1 and an indoor dipole. Ian's UK call is G0WHX.

The Reverse Beacon Network proved everything was working!
Sunday 2nd January marks the QRPARCI New Year's Day Sprint, but I really didn't expect to hear anything from the US due to rotten HF conditions. If I do I'll update the blog!

So, I heard a lot more stations than I worked, but I had fun – which is what it is all about.