Monday, 12 November 2012

Short path propagation charts from the UK


I have now updated my short path HF propagation charts for the UK for the next three months – November, December and January.

These have been created using the latest smoothed sunspot numbers from NOAA in the US and HAMCAP.

October was a fantastic month for 10m propagation with most of the world being workable at times. Early November saw a dip in the solar flux index, which manifested itself as poorer conditions overall.

But the flux has been climbing steadily over the past few days and is back in the 130s again so 10m is opening up nicely.

We just have to worry about solar flares and coronal mass ejections, which could be a fly in the ointment. Solar flares can bring short-lived D layer absorption, while coronal mass ejections, if earth facing, can bring about depletion of the F layer for many days.

Look out for a high solar flux index (>120) and a low K index (0 or 1) at www.solarcycle24.com for the best HF conditions.

The low bands are also coming into their own with the extended periods of darkness in the northern hemisphere.

Keep an eye on 80m – there will be good openings on 80m, and 40m has been open to parts of the US way past sunrise over the last week.

December should be a good month for the low bands, including Top Band (160m) although probably not as good as we have seen a few years ago around solar minimum.

The November propagation chart can be found at: www.infotechcomms.net/propcharts/november/ 

A link to all of the charts can be found top right.

Monday, 29 October 2012

Video of trip to K6KPH, California

I was lucky enough to visit the Maritime Radio Historical Society's old KPH sites at Bolinas and Point Reyes, California, in September.

If you haven't heard of these they were the transmitter and receiver sites for KPH - the mighty Pacific coastal station that sent Morse code and RTTY to ships and point-to-point services until the late 1990s.

Both sites are now restored and they also run K6KPH - an amateur station. They were kind enough to let me operate some CW as well, letting me make contacts across the USA on 14MHz.

You can find out more at: www.radiomarine.org

I shot a seven-minute video while I was there too - you can see us working G3LDI back in the UK on 20m CW. Go to https://www.youtube.com/watch?v=Wj-IwYPrtTM


More free propagation books

The late Bob Brown NM7M was an expert on ionospheric propagation. He wrote a number of great books and two of these are now available as free downloads on Carl K9LA's site.

The first is the The Little Pistol's Guide to HF Propagation

The second, on Top Band (160m propagation), is NM7M The Big Gun's Guide to Low-Band Propagation

Carl has a lot more useful information as well - see just go to http://myplace.frontier.com/~k9la/index.html

Steve G0KYA

Friday, 12 October 2012

RSGB Convention, October 2012

I will be giving two presentations at this year's RSGB Convention - one on using HF propagation prediction programs and the other on modelling antennas using MMANA-GAL.

I have made the presentations available as PDF downloads should anyone want them. I'm not sure they will make a lot of sense without the accompanying talk, but you are welcome to them anyway.

Don't forget there is a free book that you can download that explains a lot about HF and LF propagation - see the link on the right.

Here are the links: 



Monday, 6 August 2012

Special Olympic call – GO0KYA

To celebrate Great Britain hosting the Olympic Games we are allowed to apply for a special notice of variation to our licence. This allows us to add the suffix “O” to our calls.

So until early September I can use GO0KYA. I tried it out the other day and within half an hour on 40m CW I had worked the Netherlands, France, Czech Republic, Germany and Belgium.

But today I had a great idea. To celebrate nearly two years, and sales of more than 2,000 copies, of my book “Stealth Antennas” I'm going to switch to my indoor parallel-fed dipoles or MFJ-1786 magnetic loop, turn the power down to 5W and work QRP with the call.

I'll try and operate around +/3 KHz of the CW QRP calling frequencies on 40, 20, 17, 20, 15 and 10m.

I plan to try and do this at least once or twice a week and I'll add the times/bands of operation to the top of this story each time.

This idea was inspired by John N8ZYA in Charleston West Virginia, who is featured in the book and works stations using Isotron antennas mounted indoors. And yes, he does work lots of DX!

Be good to work you.

Steve G0KYA 

Update 6/8/12
Well, great evening. Condx not too good and lots of noise/QSB but worked: RY7G, OH2NOS (10W his end), OM3CAZ, OM8RA, R6AF, HA5AEK, IT9BUA (QRP), EA8AGF (QRP), S51WO (17m) and the highlight - Taka JA0FVU (17m), otherwise all on 20m QRP 5W from an Icom 756 PRO 3. Using a new touch keyer so a few mistakes! Mostly used the outdoor 20m M0CVO Windom (OCF). One or two were with indoor dipole, but needed a little more oomph. Will be on the air again soon.

Update 16/8/12
Had another session with the Olympic call today and worked R10RLHA/1 (Russian Lighthouse), RN3DMU, UA4NE/P, R200V,HG20SD, CT3AS, 5N7M (Nigeria), EW8O and OM3KFF. A couple were on 5W, but the majority on 50W. I have put the Western HF10 dipole back up in place of the M0CVO Windom as I had to repair the 10m fishing pole support - works well on 20m. Not so sure about 15m though! Very pleased about Japan and Nigeria.
 

Thursday, 2 August 2012

UK propagation charts for August 2012

It may be summer, and the Olympics are in full swing, but we can’t really expect to see record-breaking propagation on the HF bands in the Northern hemisphere.

This often puzzles new (and not so new) hams. After all, HF propagation relies on sunlight and we have that in abundance in the summer.

Unfortunately, life is not that simple. While increased UV in the summer is guaranteed, as the angle the sun makes with the ionosphere in the northern hemisphere is increased, you actually get less overall ionisation of the all-important F2 layer.

This is due to a chemical change in the composition of the F2 layer in the summer compared with the winter.

There is an increase in the molecular-to-atomic composition of this layer in the summer, which makes it harder to ionise. As a result the F2 critical frequencies in June can be half what it they are in January.

This effect is called the Winter Anomaly.

At the same time D-layer absorption is very high in the summer, especially around local noon, which gives us a double whammy – lots of absorption and low F2 critical frequencies.

The net effect is that the bands much above 18MHz can remain stubbornly closed, apart from Sporadic E (Es) openings, which by August are less prevalent. And the lower bands are also less useful during the day due to absorption.

For this reason stay away from 80m (3.5MHz) in the daytime – 40m will be better around the UK as long as the critical frequency stays up near 7MHz. Twenty metres (14MHz) will probably remain the most reliable DX band both during the day and night, although don’t write off 18MHz (17m).

Better HF conditions will start to reappear in September – sunspots, solar flares and coronal mass ejections (CMEs) willing.

Don’t forget there is a free book about HF propagation available to download on the right.


Go to the August propagation charts from the UK

or select another month

Steve G0KYA



Thursday, 5 July 2012

UK propagation charts for July 2012

There is an old Chinese curse that says "May you live in interesting times". I thought it was a greeting, but apparently not!

Well, we are living in interesting times as far as HF propagation goes.

July is usually in the middle of the HF summer doldrums - not really good conditions to speak off, but with some Sporadic E (Es). But this month is being characterised by a mass of solar flares, coronal mass ejections (CMEs) and high solar flux index (SFI) levels.

So while high SFI numbers usually indicate good conditions on the upper bands, the flare actvity is causing havoc with the bands shut down and lots of noise. Couple this with summer thunderstorms (Medium Wave was just a wall of crashes and bangs on Thursday 28th June) and it is hard to know what to work.

But in amongst all this there are good openings to be had. On 4th July I worked K2K in New Hampshire on 15m CW. This was a station being run for the US Independence Day and the prop charts would suggest that no path would have been open on that band and at that time ((1415hrs GMT).

Others are chasing 1A0C - The Order of Malta’s Italian Relief Corps (CISOM)- which is in Rome, not Malta by the way. Its signals have ranged from barely audible to S9+ depending on the solar flares and CMEs.

The best advice is keep on eye on the solar data at www.solarcycle24.com, and don't write the bands off too soon. And if you don't know what SFI, A and K indices are, take a look at the free HF Propagation book listed on the right.

73 and gud DX! Steve G0KYA

Go to the July propagation charts from the UK

or select another month


Monday, 18 June 2012

So you want a budget shortwave receiver?

Had a phone call today from a guy who was 72 and wanted to get back into shortwave listening. He said that he used to own a Marconi CR100 receiver and had things changed much?

Woo! Not much!

Anyway, after a chat he said he wanted to buy a short wave receiver, but didn't have a clue where to start and didn't have too much money. So, what to recommend?

My first reaction was to suggest a used Yaesu FRG-7700 or FR-100, or perhaps an Icom IC-R75, but these were out of his budget and he preferred new anyway.

And then it dawned on me. What about a Degen DE1103 or a Tecsun PL-600?

For those who aren't familiar with these they are both Chinese-built portable radios that cover from Long Wave to 30MHz and cost less than about £60.

Now, I know what you thinking, the best bet would be to go for a dedicated communications receiver, but for £60 brand new – I don't think so.

I own a Degen DE1103 and it is actually not bad at all. I have often listened in to various amateur QSOs with it, including CW and considering its size and weight it does quite well. It will also pull in BBC Radio Wales on 882KHz medium wave, broadcasting from Washford, Somerset, during the day at a distance of 212 miles from here in Norfolk.

It can also pick up VOLMET transmissions on SSB and lots of short wave stations, just using the whip. You can attach a longer wire antenna – it has a socket on the side, which I would recommend as it is less prone to overload. According to some reports the whip goes through a FET amplifier so overloads if you connect a wire to it..

Even using the socket, you may need to switch it from DX to Local thought to avoid overload.

It comes with a velvet carrier bag and rechargeable batteries for about £60 delivered (search Ebay). There are plenty of reviews of the Degen, especially on Eham.

I also have a Tecsun PL-600 on order which has a similar spec so I'll post a review of that when it comes.

So yes, things have moved on a bit since the CR-100, but in some respects the hobby is cheaper now than it ever was. And things are more portable too!

Thursday, 3 May 2012

UK propagation charts for May 2012

Solar conditions continue to look dismal, although the solar flux did get up to 149 on 21st April. This coincided with our entry for GB0CMS on International Marconi Day. And yes, you could see the bands hopping with contacts into Barbados and central Australia.

But now the SFI is down to 100-120 again.

Cheer up though - May marks the start of the Sporadic E season in the Northern Hemisphere so 28MHz and 50MHz will be humming at times.

This rather suggests that F layer propagation on 28MHz is non-existent. Not so - the 706T DXpedition to Yemen has been romping in to the UK on 10m CW for large portions of the day. Not terribly loud, but definitely workable once the pileups dry up a bit.

73 and gud DX!

Go to the May propagation charts from the UK

or select another month

Monday, 23 April 2012

GB0CMS makes nearly 500 contacts in 40 countries.

NARC member and local TV weatherman Jim Bacon, G3YLA,
operating the Caister station GB0CMS. (Steve Nichols G0KYA)
I was part of the team that operated GB0CMS in Caister (Norfolk) on Saturday as part of International Marconi Day. We had two stations - one on 40m and the other on 20m, operating both CW and SSB.

It turned out to be our best ever effort - we worked 487 hams in 40 countries and got as far afield as Austraila (VK5), Barbados (8P), the US (out to Ohio), Canada and Asiatic Russia (UA9).

The reason I'm telling you this is because we tried a new antenna for 40m - the W5GI "Mystery Antenna".  In fact, I only finished making it a day or so before the event so it was largely untested.

I've used one of these at home for a while and it works very well on 80m and 40m, especially if you can't fit an 80m dipole in. You can find out more on my W5GI post above, but everyone who used it was impressed and we got some very favourable reports. I find at home that it often breaks pileups on 40m even though it rests on the apex of the roof tiles!

On 20m we used my vertical end fed half wave (EFHW) design, but with a few tweaks. To stop RFI, which has plagued us in previous years, we mounted both antennas further away and I added four 10ft ground radials, earthed the matching unit to the screw-in base mount and also put a choke (line isolator) about 20ft back from the antenna. The radials are not as crucial as with a quarter wave design as it is a high impedance feed point. However, a few won't hurt and neither will the earth. The choke stopped currents flowing on the braid back to the radio. If I am operating just one radio this isn't quite so necessary.

It did the trick and we were able to operate the two stations with no mutual interference and no lost keyers or interfaces when RF gets into the cabling.

If you worked us on Saturday take a look at this short video shot by Kevin M0UJD.

Thursday, 5 April 2012

Titanic 100th anniversary book - now available as an ebook too

The book "The loss of the Titanic - its story and lessons", which I helped republish, is also now available as an ebook as well as a paperback - just ready for the 100th anniversary!
Lawrence Beesley was a science teacher, journalist and author who was a survivor of the Titanic tragedy in 1912. In this dramatic real-life tale Beesley tells first hand what it was like to be on the Titanic as it plunged into the icy waters of the North Atlantic on that fateful night.
As well as describing the voyage, the collision with the iceberg and the subsequent sinking, Beesley documents what could have been done to save the 1,500 plus people who perished.
Cover of Titanic bookHis account, and others, resulted in many changes to maritime law and procedure in an effort to make sure that a disaster of Titanic’s proportions should never happen again. “The loss of the S.S. Titanic – its story and its lessons” was first published in 1912, shortly after the disaster.
Now republished by InfoTech Communications, ahead of the 100th anniversary of the accident, the 116-page paperback book is available via Lulu.com, delivered straight to your door wherever you live in the world.
Find out more

Thursday, 22 March 2012

Keep Calm and Work Some DX


This is a bit of fun. It is a take on the British WW2 "Keep Calm and Carry On" posters.

"Keep Calm and Carry On" was a propaganda poster produced by the British government in 1939 during the beginning of the Second World War, intended to raise the morale of the British public in the event of invasion.

Seeing only limited distribution, it was little known.

There were only two known surviving examples of the poster outside government archives until a collection of about 20 originals was brought in to the Antiques Roadshow in 2012 by the daughter of an ex-Royal Observer Corps member.

But now you can wear your own "Keep Calm and Work Some DX" T-shirt, baseball cap or own a mouse mat thanks to Cafe Press.

See www.cafepress.co.uk/theradioroom

Tuesday, 6 March 2012

Using MMANA-GAL for antenna modelling


I gave a talk on antenna modelling using the free MMANA-GAL software at my local Amateur Radio Club. It looks at what MMANA-GAL is, how to use it and then a number of different applications.

Some of these are useful and surprising - like how to optimise a 40m off centre fed dipole (Windom) so that you can get 15m. And how mounting an antenna as an inverted V can seriously change its radation pattern or number of bands available.

It also asks the question is the G5RV really a good multiband antenna? Why was my W3EDP end fed better to the south-east and south west and rotten to the north. And does the DL7PE Microvert radiate off its feeder?

Download the presentation in PDF format with the notes included (8.8Mb).

Note: I have also made available a Zip file with some .maa files including the End fed Half Wave, Rybakov vertical, DL7PE Microvert, 80cm magnetic loop, 65ft Inverted L, EH antenna, 20-15-10m trap dipole, 80m OCFD (Windom) and an experimental W5GI mystery antenna file. Download the MMANA-GAL antenna files.

Thursday, 16 February 2012

Podcast: HF Propagation, February 2012


In this month's podcast I look at current solar conditions and how the solar flux index has actually come down - have we seen the peak of cycle 24 or is there more to come? Also, I look at the geomagnetic figures behind last month's visible aurora. And do we really need high solar flux numbers to work DX on 10m - you might be surprised. Lasts about 6mins 15secs.

Click on the headline to listen to the programme online or if you prefer to listen to it on your iPod search for G0KYA on iTunes.

Monday, 6 February 2012

UK propagation charts for February 2012


Solar conditions have declined over the last month. Just a few weeks ago we were suffering from geomagnetic disturbances, with reports of aurora being seen in northern England.

And now we have seen the solar flux fall to around 100-110.

This doesn't bode well for the rest of the cycle, although there is still plenty of DX to be had. Just the other morning I heard a station on from Tinian Island, Marianas on 10m SSB. He peaked at 55-56 before vanishing. In case you have never heard of Tinian island it is where Enola Gay set off from for Hiroshima in 1945.

Other DX that has been romping in includes the VP6T DXpedition to Pitcairn Island and the HK0NA Malpelo DXpedition near Columbia.

We may start to see the best of the low-band DX (80m and 160m) fade out a little as we head towards spring, and 10m may not play ball as much if the flux remains down below 120.

But keep an eye out as there will be plenty on the other bands.

Go to the February propagation charts from the UK

Tuesday, 3 January 2012

UK propagation charts for January 2012


Good solar conditions continue and we seem to have gone through quite a long period of settled geomagnetic conditions, which has helped no end.

The solar flux index has hovered around the 130 mark with no really large fluctuations and as a result we are still seeing the higher bands come to life, notably 10m.

But this is really the month for good low-band openings - 160m, 80m an 40m.

Tony G3ZRJ reported hearing long delay echoes on 80m at about 2100z on 1st January 2012. These are either signals coming around the world "the wrong way", or aided by magnetospheric ducting, or some other form of propagation that we don't really understand.

Whatever, it makes for some interesting effects. You can read more about one ham's views on LDEs here.

Just want to take this opportunity to wish you all a happy new year and remind you that you can still download a FREE guide to ionospheric propagation written by Alan Melia G3NYK and me.

Go to the January propagation charts from the UK