Late night edition.

It's been a long day here at Copper Mountain Headquarters!  So long, it's nearly eight o'clock that I am writing this.

The reason?  Well, that is a long story.  It started with my noticing the vertical delta loop was a little higher than usual in SWR during very wet weather.  It is usual for the matching to change a little in such weather, but now I was seeing 1.5:1 at 14MHz, and something similar at 28MHz, the first harmonic.

Eventually, I found a break in the wire near the feedpoint.  Nothing to complain about after five years or so of swaying around in the wind, often violently.

After repairing that, I applied the SARK analyser to the antenna, to find that, whilst 14MHz was now OK, 28MHz was way off, at about 2.5:1.

This is where things ended up wasting a lot of time.  I changed the homebrew 6:1 voltage balun for a commercial current version.  I knew this gave a higher resonance point, so I added a length of wire in the centre of the base (radial) wire until the match was very good at around 1.14:1 at 14MHz.

But sadly, 28MHz was still way out, although with a 300Ohm twin feed, this is of essentially no consequence as losses in the line are tiny compared to coax.  I just don't like using a tuner.

I then slowly came to realise, as the sun went down, that the original, homebrew balun could have water in it.  Any change in antenna characteristics should first cast doubt on any balun in use.  If only I remembered this at the time! I had taken a lot of time to make a high quality balun, but had somehow forgotten to put drainage holes in it.  I do use watertight boxes and a stone cover, but water always gets in slowly.

I opened the cover of the balun to find - yes, a pool of water in the bottom of the box!  Arrrghh!  I had wasted all that time matching the antenna to the commercial balun, and now I had to undo all the self-amalgamating tape, remove the long wire and restore the antenna to its original dimensions!

Anyhow, as it went dark, I had everything reconnected, weatherproofed and the balun covered with plastic and a ridge tile.  I also drilled small holes in the bottom that let water out, and only the very tiniest insects in!

SARKPlots sweep at 14MHz.

Same vertical delta loop at 28MHz.

The result is that I have, once more, a vertical delta with a 1.2:1 match across essentially the entire 14MHz band.  At 28MHz, normal operation, with a SWR lowering across the whole band, is restored.

Phew!  Now for some wine...

22 Minutes of WSPR

Last evening, having some time to wait around for family, I went to South Stack on Holy Island, which is part of the EU-124 coastal island groups under IOTA.

Holy Island, part of the wider EU-124 group.

Unfortunately, the IOTA system shows weaknesses with EU-124, in that Holy Island is connected by fixed road and rail infrastructure that renders it, to all practical effects, part of the larger island of Anglesey (which is considered part of the UK mainland, itself a bone of considerable and long-standing contention).  Compare that with another EU-124 member, the offshore reef we call 'The Smalls', and that is found to be over 28km out to sea!

The Smalls reef.  Getting here is almost impossible for most.

Anyway, I decided to run WSPR around the sunset period.  The antenna was not as well matched on this very ancient rocky sea cliff as it is down on the seawater-soaked sand, coming in at around 1.5:1.  I sent 1W at 14MHz out of the TS480 in the boot, and then went for a walk.

Sea cliffs at South Stack. 

Twenty-two minutes later, I was really quite pleasantly surprised at how well the stick antenna did.  To all intents and purposes, it looked on the map as though I was operating the delta loop back at home.  I even manged to get to DP0GVN twice, with a best signal of a very respectable -16dB SNR.  It might be considered nothing special, until you consider the absolutely terrible band conditions at present!

Reception reports for 1W, stick antenna on the car, 18:12-18:34UT 2018 Sept 27

Nice weekend, and vermin.

After a week of heavy winds and rain, we finally enjoyed quite nice weather for the centenary of the first direct Wales - VK contact over the weekend.

Unfortunately, the bands were terrible!  Kp was about 4, with the SFU bottoming-out at a mere 67.  Those on SSB were essentially finding nobody to talk to above 40m all weekend long. Luckily, a contact with VK was eventually made.  WSPR managed to get the message about our event rather more effectively, spanning the globe on 1W.
 
Here's my daughter, MW6PYS, who did some digital work, at the Cefn Du Marconi site, near Caernarfon.  I was pleased that she asked to go, rather than being pushed into it!

Sunny, but cold, at GB2VK.

After that event, I came home to find 12m was very active on Es yesterday.  Everything was working fine with the station.  Then I casually went to check things out in the garden, to find two coax outlet points chewed nearly all the way through!

I have always expected that a rat, mouse or some other invader might chew on my coax, but it has never happened in over 7 years of operating here.  What could be to blame?

The nibble marks were relatively small, and both cables had been chewed at the point they entered the wall.  It didn't look like the work of a rat, not least because a rat would not have been able to chew at that height, and in that way.  Rats also sharpen their teeth on harder material than very soft coax.

I thought it could be a rabbit seen in the garden, but I have had rabbits around for years as well.

Nibble, nibble!

It seems that the teeth were very small, so I think it was a mouse or similarly minor rodent.  I have been doing some maintenance on the house over the summer, and I think I may have made it more difficult for mice to get in to the roofspace through holes in old timber facing boards.  Well, that's the latest theory, anyway!

Luckily, one coax was redundant, and the other, to my 12m Yagi, had plenty of excess length, so it was easily cut and reconnected.

I've now tried to discourage further nibbling by wrapping each coax in split water hosepipe, and then wrapping stainless steel wire mesh around that.  Later, I will be buying an air rifle for a more permanent solution!

Protection until I get a gun!

GB2VK - Marconi Centennial,1918-2018.

This weekend is an incredibly momentous one for Wales, which I deliberately set apart from the rest of the UK because it's not often our forgotten nation gets to take credit for anything!

GB2VK finalising set-up in very inclement conditions, 21/09/2018.

On Sunday, 22nd September, GB2VK will commemorate the 100th year since the first direct, non-relay contact was made between the UK and Australia.

Of course, even a radio message sent from Wales had to be changed to 'England'!

Even at solar minimum these days, we can easily make some form of contact with VK using just millwatts of output.  Back in 1918, when even producing radio waves of sufficient frequency for long distance contact was difficult due to mechanical limitations, it took the Cefn Du (meaning 'black hill) transmitter, a few miles to the north of Caernarfon, a staggering 160kW at LW frequencies to make the VK contact!

The transmitter at Cefn Du, lying at 1000 feet (300m) above sea level on a gentle mountainside overlooking the Irish Sea, was keyed remotely from Tywyn, a tiny settlement 60km to the south.

The antenna at Cefn Du was an enormous inverted-L of some 1100m in total length.  Operating frequencies were experimental, and varied typically between 50 and 100kHz.  With so much power feeding the antennas, local people claimed that steam could sometimes be seen rising in winter from the boggy ground during transmissions!
 

 

One of the ten, 400ft (122m) tall steel antenna support masts.

The Cefn Du transmitter site, Wales in 2017.  Still largely as it was in 1918, minus the equipment!

One of the many massive concrete stay cable anchors at Cefn Du, 2017.

Concrete base and bolt anchors for a steel tube antenna support, 2017.

Remarkably, after 100 years, the stay cables and huge ceramic egg insulators are still present, lying where they fell when they were cut down in 1939.

John Parry, a former Navy radio operator and, later, university electronics technician, working CW on Marconi Day, 2017.

One of the rooms at Cefn Du transmitting site.  Now in use to stable horses.

The messages sent between Wales and Wahroonga in 1918 was a politically-motivated note of mutual appreciation for each nation's part in the Great War, support for which was waning in Australia at the time.  The war was to end just a few weeks later.

The messages were:

1          1.15pm Sydney time.
            "I have just returned from a visit to the battlefields where the glorious valour and dash of the Australian troops saved Amiens and forced back the legions of the enemy, filled with greater admiration than ever for these glorious men and more convinced than ever that it is the duty of their fellow-citizens to keep these magnificent battalions up to their full strength. W.M. Hughes, Prime Minister."
2          1.25pm Sydney time.
            "Royal Australian Navy is magnificently bearing its part in the great struggle. Spirit of sailors and soldiers alike is beyond praise. Recent hard fighting brilliantly successful but makes reinforcements imperative. Australia hardly realises the wonderful reputation which our men have won. Every effort being constantly made here to dispose of Australia's surplus products. Joseph Cook, Minister for Navy."


The event, taking place in a very rural, quite remote area of Wales, was of enormous interest to schoolchildren at the time, finding themselves living near to the very latest technological advances in communication. Falling victim to rapid developments in radio, and heavy ice storm damage to cables, the station was dismantled in 1939.

Marconi's voice can be heard at the unveiling of the memorial (pictured below) in 1930 at Wahroonga.  Note how remarkably good he was at taking credit!

 https://soundcloud.com/essex-record-office/marconi-speech-part-1

https://soundcloud.com/essex-record-office/speech-by-marconi

Statue of Mercury, commemorating the 1918 contact, in Australia.

Service suspended.

Yes folks,the UK hurricane season has started in earnest!

Although technically we don't get hurricanes in the UK, the wind speeds we experience are of hurricane strength.

Eleven months ago, we experienced one of the worst storms in recent years, ex-Hurricane Ophelia, which seems to have begun a trend of tropical storms that turn northwards towards the UK, rather than running west towards the Caribbean, as is more usual.

Storm Ali, 19/09/2018.

Yesterday (20/9/2018), we saw ex-hurricane Helene swing by, bringing gusts of about 90km/h. A typical windy autumn day in Wales.

This morning, the centre of Storm Ali is running up towards Northern Ireland and Scotland, with winds here in Wales already up at about 120km/h in gusts.

Force 11, and rising...

Although all the antennas remain flying in these conditions, operating during these winds isn't very well advised.

Normal service will resume later in the day.  Maybe...

FT8 Call.

As a piece of software in development, FT8 Call is constantly undergoing frequent changes and updates.

I was prompted to look at FT8 Call again yesterday, having left it alone for some time due to the lack of users.  Most signals on there seem to be US-based, with few from anywhere else.

Much as I like the USA, I've long ago become tired of the bias in QSOs with that country.  These days, I've returned more to my original interest of working to the east.

The latest FT8 Call user interface is very nice and uncluttered.  There are still not many users, though.

But whilst I sent out a few test calls and beacon transmissions, a slight problem with FT8 Call struck me.

Unlike modes like ROS and OLIVIA, FT8 Call transmits with what appears to be a much higher duty cycle.  Whilst modern rigs are not exactly taxed by running hot, it is something to try and avoid where possible.  It's also regrettable that the de facto operating frequency simply juts into that conventionally used for JT9.

Some ROS operating earlier today.  Great weak signal chat mode, but very few users now.

Perhaps the best mode in terms of duty cycle is HELL, which has reasonable weak signal capability, though nowhere near as good as OLIVIA.  You can send HELL all day, and the rig will not break out a sweat.  But these modes also suffer now from very few users, which has become much worse since FT8 swept in from the west.

Certainly, FT8 Call has some potential.  I'm not persuaded yet, with its very slow transmission rate (a couple of lines takes over two minutes to send in several 15-second 'overs' that split the message into chunks) that it offers much over and above PSK, which we can run at various speeds, according to conditions.  Certainly, I strongly prefer the much more human-centric nature of OLIVIA, HELL and the rest.  You can comfortably type in some free messages and have plenty of time to correct any mistakes.

After writing most of this post, I came across a characteristically interesting video from OH8STN, using FT8 Call to send 'critical', brief update messages from his field operations.  Whilst I do tend to cringe a little bit about ham radio being described as some form of military or emergency platform, Julian has a point in that very quick messages are usefully sent using FT8 Call.

Overall, FT8 call has to show me something more than just the fact that it's new to persuade me to use it.  I'll keep an interested eye over developments, but I think other modes have offered much better solutions, and for some years by now.

Hurricane Florence - and radio silence?

Yes folks, despite The Donald's energetic denial of climate change, Hurricane Florence - the most powerful storm ever to hit the US east coast - is already causing the evacuation of at least 1 million people.

Every year, there are people whose sole purpose it is in life to portray ham radio as something that makes a real difference to lots of people in an emergency.

Get out your radios!  Or, just run... Image: NASA.

Every day, there are Maritime Networks and such stuff that endlessly call out for messages from boats out at sea.  Pretty much all the time, nobody does actually call in, not least because there are so many other simple, automated and effective position-relaying systems available at modest cost, and even keep working when they fall into the sea - unlike a HF rig!

With recent earthquake events, there have been the rather ridiculous situations where somebody with not much brain in the USA decides with some friends to try and keep the very middle of 14MHz clear of ham traffic 'in case' someone in Nepal wants some help.  So it continues for days or weeks on end, helping nobody except those desperate people who adhere to this ludicrous vision of ham radio's purpose.

Rather oddly, though, QRZ.com and the usual ham outlets are not (yet) full of EMCOMM people with fluorescent jackets claiming that they will save the world with their 2m FM rig, even though the extent of devastation is clearly going to be enormous.  And there is plenty more action forming out at sea, as I write.

We'll see how many people EMCOMM saves this time.  My prediction is: nobody at all.

But if you really want to know how radio will overcome your lack of health insurance, have a dull few minutes looking at this video:

Hurricane Alley today.  Image: earth.nullschool.net