WSPR Mobile!

The move towards faster, cheaper, less fixed operating continues apace!

With some spare time this evening, I brought my trusty Raspberry Pi out of the field location and out into the car.  My own car is not very new, so doesn't have USB power outlets.  Instead, I just installed my own twin 2.1A outlets earlier this afternoon.

Conditions on HF remain very poor following a CME impact a couple of days ago. But this didn't stop some very interesting findings coming out of my expeditionary work with a 14MHz whip on top of the car, and my Kenwood TS-480SAT in the boot.

Out over the sea!  WSPR mobile with a Raspberry Pi.

First, I set up in what the English folk call 'Bull Bay', more properly known in Welsh as 'Porth Llechog', which is a cliff side position overlooking the Irish Sea from NW to NE.

Then, after a while, I ascended a mile or so inland, but gaining about 250 feet in height and moving onto what is probably amongst the world's most conductive ground - good old Parys Mountain, but not at the home QTH, but on the mine waste itself.

The results speak for themselves.  Look at the difference between coast and the copper hill for spots received by TF1A (note: the time span of the test is only about 40 minutes, so propagation doesn't account for the change, more especially as the move from coast to hill took just 4 minutes).

First four spots at the coast.  Last three, on top of Parys.

More coastal WSPRing.

Another fairly warm afternoon on a long, bank holiday weekend led my daughter and I down to one of the local beaches earlier today.

Playing radio when out with the family never really works out, so I decided to deploy my mobile stick for 14MHz and just let WSPRlite send some signals to the world whilst I built rock castles with my daughter.

The location is not exactly outstanding, with only a limited open sea view, and with plenty of tourist vehicles in the car park.

I found some difficulty matching the antenna properly.  It struck me this was likely due to common mode current on the coax feed.  After winding a simple multi-turn 'air' balun, the problem went away, the matching was nice and sharp, and reached a low ~1.2:1 SWR.

I ran for about 1.5 hours, and was surprised to find my £20 mobile stick did substantially better than G3CWI and G8LIK, who are both pretty good stations with full-sized wire antennas.  Shorter DX stations were stronger to those two stations, but that is of no interest to me, because my stick was getting to places, under very tough geomagnetic conditions (Kp=4), that they weren't.

JT9-fest!

Yesterday morning, I decided to tune in to 14.078MHz - the JT9 portion of the 20m band that has, since the advent of the mindless FT-8, become almost dead.

Imagine my surprise to find this waterfall:

JT9 is back!

The action was all part of a very worthwhile effort by the Russian Digital Radio Club to promote 48 hours of JT9 activity.  I'm not a contester, but I do applaud the 'most kilometres' scoring system used.

I spent quite a lot of the time I had free on Saturday working long-haul DX into Asiatic and Pacific regions of Russia, which gives the mind a wonderful trip of imagination to far-distant lands.

JT9's slowness is, to me, its strength.  Apart from yielding much better DX than FT-8, it gives you time to look operators up on QRZ.com, think about propagation effects between stations, and allows you to 'feel' the propagation changing as the planet rotates.  It's a mix of experiences that the manic FT-8 just doesn't give you.

I hope we see much more JT9 on the bands once more - it's a great mode.  Heck, I will even become a contester in the next digi-event! For the moment, I've joined the RDRC as member  number 1084.

1000 QSL cards: free?

Over the past couple of weeks, I've been operating under the SES of GB8WOW, commemorating the 41st anniversary of receiving the 'Wow!', unexplained radio signal at Big Ear observatory.

This SES has been very popular, with a lot of stations calling in.  These days, due to postage and time constraints, I don't normally bother with physical QSL cards, but prefer LoTW for its speed and simplicity.

Remembering the WOW! signal with GB8WOW.

I was then surprised to receive an e-mail from Gennady, UX5UO, who makes very fine QSL cards that I've used for my native callsign. 

Gennady was offering 1000 'free' QSL cards, subject only to paying postage when I received them. Quite an offer, as the basic single sided cards on offer typically cost £35.

Alas for poor Gennady, who is a very good and honest businessman, I am rather cautious about 'free' offers, not least because I have no real idea how much the postage cost would eventually prove to be.  So I politely declined the offer.

I'm not sure if the 'free' offer indicates that QSL card printing has dwindled to alarmingly low levels these days.  Most QSL bureaus complain of ever-increasing workloads, and ask operators to reduce their throughput.  Perhaps Gennady has spotted my operating a few SES calls this year, and hopes to attract an order for paid-for cards next time?

Anyway, if you want good quality QSL cards with excellent colour accuracy (that is not easy for my particular QSL card, and others have failed to do it properly), then do visit Gennady's site, with whom I have no association other than as a satisfied customer.

At the coast: ham radio as it should be.

This week, I have some spare time.  The weather is at the stage where it's still very warm, but the spirit of autumn is there, in the wind and the sky.

Yesterday afternoon was perfect for a fairly brief test down at the coast of my magnetic loop using WSPR.  Not only did I get to obtain some valuable results, but also a nice conversation with a tourist and some geography students from Durham University.  Very pleasingly, the visitors were willing to ask what I was doing with my strange copper tube, and take a genuine interest in how WSPR worked in tandem with the internet, and how they could see the results on my mobile phone.  There is something to be learned, there, about how to improve our relations with the general public...

My homebrew magloop and stand all fits neatly on the back seat.

Rather than simply place the loop somewhere and look at the global results, I had a very specific aim in mind.

This aim arose because of the following:

(1) The best one can generally hope for when operating down at the seaside is about 180 degrees of water in front of you.  A lot of good locations are not readily accessible, and one has to settle for the few places with reasonably easy car access.

(2) The north coast of Anglesey is ideal for transmitting to and receiving from stations located in Iceland.

(3) The Icelandic stations have recently been reliably available at all times.  The availability of WSPR stations for anything more than about a day is a big problem.  Very few stations are listening and/or transmitting over long timescales, which makes identifying patterns hard.

(4) A vertical magnetic loop works best with its two vertical sides aimed at the location of interest, because this is the plane where a strong, dipole-like, vertically polarised figure-of-eight pattern is produced.

As it turned out, the tide was just past its lowest state on a spring tide, which wasn't ideal.  Even so, I had a good 45-degree swathe of open water centred on Iceland in front of me, so I set up the WSPRlite, to see how far 200mW would go through what many people still call a 'dummy load'.

The stand I built, which includes levelling feet, proved to be adequate if large stones were placed to stabilise it, and a single kite string used to stop swaying.  In general, the stand needs to change to a large tripod, with its apex at the top of the magloop so that it will be much more easily deployed on uneven ground and have more resistance to wind, without stones and string!

Not the best tidal state, but it was clear to Iceland!

To ensure some kind of context, I also set up my rig back home to send an oscilloscope-calibrated 200mW at 14MHz from my vertical delta loop at the same time.  Remember that this is situated over extremely mineralised ground overlooking the Irish Sea from a 100m ridge.  On listening tests, this antenna typically gets to anything between number 8 and number 4 in the top WSPR stations across the world.

Stable in a 22mph wind - with help from rocks and kite string!

The results?  Well, let's just remember this was a 1m-per-side, 15mm outside diameter copper tube loop at the seaside, running against an 8m-tall, full wavelength wire delta loop on top of an old copper mine.

Test period = 13:18 to 15:40UT, 22/08/2018.

Magnetic loop distance from water's edge: maximum 3m, minimum 1m (0.14 to 0.04 wavelength), incoming tide.

Matching of SARK-110 analyser, air-spaced capacitor with 6:1 reduction drive: 1.15:1 SWR.

Magloop, 200mW (operating as MW1CFN):

Median SNR of 26 spots at TF1A = -4.5dB, standard deviation: 2.0dB

Delta loop, 200mW (operating as GB8WOW):

Median SNR 26 spots at TF1A = -4.5dB, standard deviation: 2.3dB

A zero difference!

For 'external' comparison, I looked also at G0CCL, which is a centre-loaded vertical monopole mounted on lots of industrial metal pipework, and has a very good performance over a long timescale.

G0CCL, 200mW:

Median SNR of 37 spots at TF1A = -5.0dB, Standard deviation of 7.5dB


As I have found before, a magnetic loop is once again definitively shown not to be a 'dummy load'.  Down at the seaside, the magnetic loop is able to match the performance of a full wave wire loop, which itself is in an extremely good location.

We have to remember - and the articles in magazines almost never mention this - that the antenna environment is absolutely crucial to how well(or not) any particular design works.  Sticking a magloop in a garden among a dense housing estate and expecting good results is a bit like trying to look through binoculars with the dust caps on the lenses!

Certainly, as soon as I re-engineer the stand to a tripod type, I will be returning to this and other parts of our coast, to see how long path compares in the autumn.  By then, it will be colder - and much windier!

What a treat!  Image:Wikimedia Commons/Arpingstone.

To put the perfect topping on a great day, an E3 Sentry AWACS aircraft flew low over me, heading out to the Irish Sea.  It's the first time I've ever seen such an aircraft, even living very close to RAF Valley.  I suspect there is enhanced interest in claimed Russian activity in this area at the moment...

Back on the magloops!

With continuing warm and fairly dry weather, attention has turned, once more, to magnetic loop work at Copper Mountain HQ!

This time, the focus is on simple portable deployment, with a loop that (just) fits in the back of the car and will go down to at least 30m, and a timber stand that gives reasonable height whilst still being fairly simple to build and light to carry around.

I'll post details on the build later.  For now, I'm starting to think about a more permanent magnetic loop for the /P station location, which will require remote tuning.

I recently bought, for £11, a 6:1 planetary (manual) drive to test on a butterfly capacitor.  Despite the fairly low degree of drive reduction, I was surprised at how very much easier it is to tune a magloop with this than without it.  With the aid of an antenna analyser, or simply a SWR meter, one can make controlled, accurate approaches to the perfect matching 'dip' without overrunning, as is almost inevitable with a 1:1 drive.

All the same, the 6:1 remains too fast a ratio.  For much finer control, this seems a good place to start. I'm quite excited to find a simple 12V,  5300:1 unit for just £23, and will let you know how I get on with it in due course.

WSPR - Choose your magnetometers with care.

I'm currently running a longer-term WSPR campaign, with a focus on the auroral zone.

I'e been scratching my head in trying to relate the Kiruna magnetometer output with changes in HF propagation.

Kiruna on 03 August, 2018.  Seems pretty quiet...

...until you examine stations at higher latitudes.

It turns out that Kiruna is too far south, even at 67 degrees north, to reveal the changes relevant to HF in the auroral zone. 

For a more reliable output in terms of effects on HF, one has to look at Nordkapp, which is at 71 degrees north.  Or Tromso, at 69 degrees north.  These stations typically show large variations in the magnetic field, when Kiruna shows almost a flat line.


So, if you are interested in high latitude WSPR, then have a look at multi-station stackplots like those available here, to ensure you have the best chance of understanding what's going on.

The First Amendment, amended.

In 1791, the First Amendment to the Constitution of the United States of America was adopted.

For those not familiar with it, the relevant text is:

'Congress shall make no law... abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the government for a redress of grievances.'

The First, however, doesn't seem to apply to the moderators of QRZ.com.  And it's not the first time it's been noticed.

USA!

 A day or so ago, I responded to a discussion on the QRZ.com forum concerning the vastly inflated prices of ham radio equipment, as compared to the exact-same products (in this case, headsets) sold to pilots.  In broad terms, a certain basic pilot's headset sold for about £110, whilst the same model sold to hams retailed for £249.

Given the safety-critical nature of a pilot's headset, you'd expect any price differential to work the other way.

Except, pilots are clever people who have a job to do.  They don't think, like hams do, that wearing a headset gives them kudos or makes them more manly.  In fact, I can tell you, as a pilot, that we spend a lot of time wishing we weren't wearing those uncomfortable headsets at all.

With plenty of aggressive US-based responses to my claim that ham outlets were treating us all as being "pretty dumb" by inflating prices to ridiculous levels, I ventured onto the likely effect of the USA's trade war against several countries.

In brief, cheap products from China will now either be unavailable, or be elevated in price due to tariffs.  Or, you will be forced to buy US-made products, which will be more expensive than what one could previously buy from abroad when no tariffs existed, or as expensive as the tariff-hit imports.

The response by QRZ.com was to delete my comment.  I couldn't really care less, other than to note that in the 'Land of the Free' - and the First Amendment - Congress may not be permitted to curtail open debate, but QRZ.com can.  Another example of how the American-dominated New Media now represents the greatest threat to free speech, by far.

As Cerys Matthews (Catatonia) once sang 'Every day when I wake up I thank the Lord I'm Welsh'.

Prejudice against the upper bands.

Hello again!  It's been a while.

I've been busy over the past week with a visit from overseas by my eldest daughter.  Messing about on boats and in the mountains was a much nicer proposition that playing radio!

Out under the Menai Suspension Bridge last week (I'm at the back, short hair!)

But wait!  Let's get back to normality.  Here comes the latest RadCom, the RSGB's rarely-interesting magazine.

A couple of interesting letters concerning the promotion of cheap, rather than massively expensive transceivers to youngsters and newcomers appear in the back page.  I was happy to see these, as I frequently decry the profiteering that takes place in ham radio whilst our numbers decline.

The response from the RSGB was typically bland, and went off message a little by promoting software defined receivers.  The letter was more about about transceivers.

What really irritated me was the RSGB's response concerning the 12 and 10m bands, which "counselled against" the use of CB-adapted transceivers for those bands in "this part of the sunspot cycle".

What?

Here's how my waterfall looks this morning at 12m:

I'm not sure why the RSGB thinks 12 and 10m are all but dead at solar minimum, because, rather self-evidently, they are not.  Less active, maybe, but dead, no.  I spend most of my time on 12m, and can definitively say that band is open just about every day during daylight, and still produces the occasional post-sunset activity.

Unfortunately, ham radio suffers from an awful lot of 'conventional thinking' that then evolves to become blindly-repeated prejudice.  Of all participants, I expect the RSGB to know what it's talking about, not get into line with all the other sheep who base their views on what they read in a book 30 years ago - a book that was probably repeating views from 30 years before that.

To anyone happening upon this blogpost by chance, I say this: if you have little or no money for ham radio, you CAN participate without being inferior in any way.  Spend some time online to see what's available, and ignore the expensive products within magazine pages.

Remember, also, this: the majority of operators are based in developed areas of the planet where high electrical noise levels and heavy, built-up environments mean they can hear much less with their £10,000 station than someone with a simple radio and wire vertical antenna in an RFI-free place.  The retired rich folk don't want to hear that, so it simply doesn't get discussed. They just continue spending ever more money.  Indeed, many won't even realise their noise problem, and many of those who do will refuse to accept someone with cheap equipment can do better than them.

Get out in the open air, and escape modern electronics-generated RFI. 

Focus also on a good environment.  That, also, gets very little discussion because the rich retired have invested all their money in a fixed, home-based station.  Get out to the fields, the beaches, the hills, the parks.  You get fresh air, and won't ever suffer the soul-destroying effects of your neighbour wiping out all the HF bands with an LED yard light, solar PV system or something equally RFI-generating.

Sure, get an SDR receiver if you only want to listen.  My £20 generic unit is almost as good as a £600 radio's receiver.  But also get trained up and get your licence.  Then you can get a CB-derived 12 and/or 10m transceiver for maybe £150 new, much less, second-hand.  There is PLENTY going on there throughout the solar cycle, and it will also teach you some patience and interest in how and why propagation changes.

Above all, don't listen to retired old men who profess to being knowledgeable when in fact they are simply blinded by their own, fixed and misguided beliefs. 

The quiet problem with WSPR.

I accidentally pressed the 'Stats' button on the WSPRnet site this morning.

What this reveals in hard statistics is what we already know: WSPR transmitters are outstripping receivers, and by some distance.

This problem is clearly linked to the availability of transmitters such as WSPRlite and similar products.

Until about early 2016, TX and RX were pretty much equal.  But not since.

WSPRlite has allowed plethora new possibilities, not least the ability to operate on USB-level powers for long periods in remote field settings.  Previously, this was effectively impossible for most of us.

But the big gap between transmitter and receiver numbers - the commencement of which is clearly linked to the onset of WSPRlite availability - needs a solution.

The best answer, it seems to me, would be to have a WSPR-dedicated transceiver that operates on USB-level power that can be deployed in the field.  It could either log spots internally for later upload to the database, or have some form of WiFi connection, perhaps via a neighbouring mobile phone with WiFi relay functions.  In all cases, a reasonable clock accuracy is needed, which could easily and cheaply be acheived via a GPS shield, or simply via the internet, which is usually more than good enough.

Altogether, I have to say I'm surprised nobody has yet come up with something like this.  Attached to a small solar PV or wind turbine, it could also solve the enormous bias in the deployment locations of WSPR stations, which are almost exclusively restricted to developed nations.

I wonder if anyone will pick up the opportunity these problems offer?

SDR Reception of WSPR

I had another play with my very cheap generic RTL-SDR unit today.

I can't say I've had a huge amount of success with HF on the SDR in the past, but I seem recently to have become much more determined to work at problems.

After a bit of running extension USB cables, and a short extension to make it to the 30m antenna connection, I managed to get SDR# to work very nicely with JTDX, via a virtual audio cable.

Screen grab of this afternoon's testing with SDR# working across a virtual audio cable with JTDX.

Straight away, WSPR decodes were appearing with quite good frequency stability for the price of the unit, and reasonably good sensitivity, though some way below a conventional 'rice box' analogue transceiver.

My aim is to run WSPR reception on a longer-term basis, as I am very much opposed to adding to the statistics of transmit-only operation using WSPRlite, which is now rapidly eroding the usefulness of WSPR.  According to one recent study, only about one receiver is running for every three transmitters.

I'm also aiming to have a system that uses much lower power than a full conventional transceiver does, for which the SDR, using 5V USB power from a Raspberry Pi or similar, is ideally suited.

I'm starting to look at the more expensive SDRs like AirSpy and SDRPlay, which ought to have better sensitivity.  But for the £5 the RTL-SDR cost me some years ago, I haven't got an awful lot to complain about in terms of general performance for the moment!