A couple of years ago, as has been recounted here many times, I wrote to the RSGB about the problem of long-term WSPR beaconing results being interrupted - sometimes for days - by the likes of RTTY and CW contests. Such interruptions also repeat most weekends. Other, similar problems have also recently arisen, due to WST-X assigning frequencie to itself.
The RSGB's response at the time was that, if any member suffered problems, they 'should QSY'. Rather obviously, this was as ignorant as it was surprising! It also tended to show that WSPR was not understood as a form of beaconing within the UK's representative body for amateur radio (would they have suggested QSYing for a 'traditional' beacon suffering interference?)
Since then, there has been no progress towards putting WSPR in a protected beacon area of the bands, despite the meteoric growth in the number of WSPR users, partly down to the availability of cheap, highly portable transmitters such as WSPRlite. Some hard-nosed people argue that WSPR is not a real beacon, and that a WSPR transmitter can't, as is clearly obviously done by a large number of people every day, lawfully be operated unattended.
This latter argument undoubtedly has some truth in it. But law does not operate in a vacuum, and must reflect pragmatic reality. The general consensus of today's reality is that, so long as a WSPR beacon is not left so unattended as to make near-immediate shutdown impossible (say, by going on holiday), then the outputs involved are, some (like me) argue, unlikely to make operation without a human actually sitting next to it unlawful. After all, OFCOM hasn't prosecuted any operator for causing 'intereference' since anyone can remember (source: OFCOM Freedom of Information Act request, ca. 2011).
The only other argument against moving WSPR to the beacon portion of the bands comes singularly from some of the crazier people in the USA. They see any form of change and protection as 'big government interference', the kind of interference such people tend to believe needs the carrying of guns to defend themselves against. Such arguments from the Land of the Trump need no further consideration.
Back in the real world, the fixed frequencies within the WSJT-X software (and others) makes coordinated changes to another set of frequencies more difficult, in that it would realistically require a new version of the software to be released, so that everyone was herded to the same watering hole. But that is easy to do - we get new software releases all the time.
Sadly, the clear problem with giving more protection to WSPR beaconing is not that it can't be done, or that it would need such progress through layers of committees as to be not worth the effort. No, the real problem is that there is no pressure from the WSPR community itself.
So I was somewhat surprised over Christmas, in correspondence with a serious WSPR user, to learn the following:
'Peter, G3XJE, is on the RSGB Propagation Committee. He's
investigating what real scientific data can be derived from the
WSPR database.'
Well, I suppose we have to welcome that WSPR is now catching the attention of the RSGB at committee level (they love committees), and by someone who appears to be a scientist in his own professional right.
To G3XJE, I would say this:
'Yes! There is an awful lot of 'real' scientific data that can be gleaned from WSPR, and I haven't a clue why the RSGB is only now taking an interest in WSPR, many years after it first appeared. Please continue to take an interest - and look at simple ways to get WSPR over to a protected area of the bands, because the current allocation is prone to interference and making the data much less 'really scientific. We all potentially stand to benefit from WSPR use, either personally or collectively.'
Monday, 31 December 2018
Sunday, 30 December 2018
12m doing well!
WSPR receive suspended today for some 12m activity.
Following is plot of FT8 signals received here (ignore terminator). Not bad for solar minimum, and nice to work John, ZD7JC again this morning:
Following is plot of FT8 signals received here (ignore terminator). Not bad for solar minimum, and nice to work John, ZD7JC again this morning:
Saturday, 29 December 2018
Grumpy old men discuss...
Whilst searching for my own instructions on setting up my Raspberry Pi touchscreen on this blog yesterday, I was very fascinated to come across something surprising.
Somehow, my blogpost about the Pi screen, either directly or indirectly, had ended-up being posted on an 'old-fashioned' newsgroup.
The discussion there was merrily taking place, apparently in some kind of belief that it took place whilst nobody other than the kind of small clique the Brits are famous for forming was watching.
From the comments, at least some of the group members are quite elderly, and have a very peculiar attitude to what they see as 'new' technology (i.e. technology that they themselves did not use over the past five decades, and, by implication, could therefore have no present or future use - or be a legitimate part of radio).
Below is a screen shot of this bizarre underworld, some of whom are apparently arguing that technology, by virtue of being 'new', is illegitimate. Taken to its logical conclusion, that would mean that, in the late 19th century, radio itself, as a 'new' technology, had no use or legitimacy (whatever that means) - a claim that was made by a few, supposedly enlightened people at the time.
I wonder how far back we have to go before a technology is useful and legitimate? Sticks and stones? They seem doomed.
I'm perfectly happy for people to disagree and be grumpy about life and my blog posts. But the second screenshot shows a much nastier side of the hobby and its participants. Some of the comment borders, or is, defamatory, and seem to repeatedly involve the same people, apparently insistent that CW is the only 'one, true mode'.
A hint to the bitter and twisted among you: create libel, and you had better have deep pockets; a blogging acquaintance of mine, less mindful of law, ended up with a (at last count) £230,000 bill for making comments she couldn't prove were true online. Repeatedly doing so against the same person, of course, makes matters considerably worse...
Somehow, my blogpost about the Pi screen, either directly or indirectly, had ended-up being posted on an 'old-fashioned' newsgroup.
The discussion there was merrily taking place, apparently in some kind of belief that it took place whilst nobody other than the kind of small clique the Brits are famous for forming was watching.
 |
| Caution: grumpy old men. |
From the comments, at least some of the group members are quite elderly, and have a very peculiar attitude to what they see as 'new' technology (i.e. technology that they themselves did not use over the past five decades, and, by implication, could therefore have no present or future use - or be a legitimate part of radio).
 |
| Taking this /P, and reporting stations heard by smoke signals is easier than a Raspberry Pi running WSPR? |
Below is a screen shot of this bizarre underworld, some of whom are apparently arguing that technology, by virtue of being 'new', is illegitimate. Taken to its logical conclusion, that would mean that, in the late 19th century, radio itself, as a 'new' technology, had no use or legitimacy (whatever that means) - a claim that was made by a few, supposedly enlightened people at the time.
I wonder how far back we have to go before a technology is useful and legitimate? Sticks and stones? They seem doomed.
I'm perfectly happy for people to disagree and be grumpy about life and my blog posts. But the second screenshot shows a much nastier side of the hobby and its participants. Some of the comment borders, or is, defamatory, and seem to repeatedly involve the same people, apparently insistent that CW is the only 'one, true mode'.
A hint to the bitter and twisted among you: create libel, and you had better have deep pockets; a blogging acquaintance of mine, less mindful of law, ended up with a (at last count) £230,000 bill for making comments she couldn't prove were true online. Repeatedly doing so against the same person, of course, makes matters considerably worse...
 |
| The strange world of a newsgroup clique... |
Overnight WSPR report, 28-29/12/2018
Geomagnetic conditions were best described as 'rough'!
This yielded plenty of spots throughout the night from a handful of European stations, with one appearance by HZ1AM (23:32UT, -25dB from 200mW), and one from W1AIU (23:46UT, -26dB from 5W).
The W1 spot is interesting, and certainly anomalous. Whilst the field had yet to fully restore to quieter conditions, the spot did tend to coincide with the restoration phase - a common finding here.
The other interesting variation to follow was that in the signal from Cambridge, UK station, G0CCL, showing beautiful peaks at (UT) midday and midnight, the midnight peak being a product of the disturbed conditions (a small number of 1W signals, sent occasionally by G0CCL, have been removed from the plot):
This is very different from a typical quiet day:
 |
| Image: IRF/Kiruna. |
The W1 spot is interesting, and certainly anomalous. Whilst the field had yet to fully restore to quieter conditions, the spot did tend to coincide with the restoration phase - a common finding here.
The other interesting variation to follow was that in the signal from Cambridge, UK station, G0CCL, showing beautiful peaks at (UT) midday and midnight, the midnight peak being a product of the disturbed conditions (a small number of 1W signals, sent occasionally by G0CCL, have been removed from the plot):
RSP1a SDR Update
I've been running the SDRPlay RSP1a for a good week or so, without interruption, on 14MHz WSPR, to assess its sensitivity and overall performance. It's apparently a good time to run WSPR, as there are no major contests to cause interference (at least, until today, when the Canadians run a big event!)
First thing to say is that the fairly complex combination of SDR, PC, and three pieces of software all working together has performed without any crashes or similar issues. CPU demand on my two-year old HP laptop varies between around 30 and 65%. The laptop does run its cooling fan more often than when not running SDR software, but it is not running continuously or very frequently.
Secondly, on the negative side, but not down to the RSP1a per se, is the very occasional failure to upload spots. This could be software demands on the CPU, some minor software conflict, or some other such issue. Spot upload failures may well happen occasionally with a simple 'rice box' transceiver and sound card interface, too.
Certainly, if there are the odd spot upload failures, then they don't seem to adversely affect overall outcomes in the DX WSPR listening challenge. Any system that can give more spots, if only sometimes, than EA8BFK is, without doubt, something to write home about!
The results over recent, full-24 hour periods are:
December 20 = number 6
December 23 = number 6
December 24 = number 3
December 25 = number 6
December 26 = number 11
December 27 = number 1
December 28 = number 9
Median outcome = number 6
So, whilst I can't take credit for anything other than putting up an efficient antenna in a good location, the RSP1a can take a lot of credit for yielding excellent sensitivity, especially when considered against its low price.
First thing to say is that the fairly complex combination of SDR, PC, and three pieces of software all working together has performed without any crashes or similar issues. CPU demand on my two-year old HP laptop varies between around 30 and 65%. The laptop does run its cooling fan more often than when not running SDR software, but it is not running continuously or very frequently.
Secondly, on the negative side, but not down to the RSP1a per se, is the very occasional failure to upload spots. This could be software demands on the CPU, some minor software conflict, or some other such issue. Spot upload failures may well happen occasionally with a simple 'rice box' transceiver and sound card interface, too.
Certainly, if there are the odd spot upload failures, then they don't seem to adversely affect overall outcomes in the DX WSPR listening challenge. Any system that can give more spots, if only sometimes, than EA8BFK is, without doubt, something to write home about!
 |
| Good result from the RSP1a on 27/12/18! |
The results over recent, full-24 hour periods are:
December 20 = number 6
December 23 = number 6
December 24 = number 3
December 25 = number 6
December 26 = number 11
December 27 = number 1
December 28 = number 9
Median outcome = number 6
So, whilst I can't take credit for anything other than putting up an efficient antenna in a good location, the RSP1a can take a lot of credit for yielding excellent sensitivity, especially when considered against its low price.
Friday, 28 December 2018
Overnight WSPR report, 27-28/12/2018
The geomagnetic field was quite disturbed overnight, briefly reaching G2 (Kp=6) levels. The aurora was predicted to be visible over central UK, but cloud prevented confirmation:
The disturbance didn't lead to any DX spots at all. But, very many spots from France and Italy were received all night long. The case of F1AGR is interesting, in that this station is heard almost daily at various points in the night, regardless of conditions. PE4BAS is also hearing him in the same way.
The disturbance had a clear effect on signals heard from Italy, in that normal propagation cut-off for that region, before midnight on the preceding, quiet days, did not occur last night:
As for the continued assessment of the RSP1a SDR, things came to an abrupt end this morning, because the WSPR DX Challenge web site is not functioning properly!
The disturbance had a clear effect on signals heard from Italy, in that normal propagation cut-off for that region, before midnight on the preceding, quiet days, did not occur last night:
As for the continued assessment of the RSP1a SDR, things came to an abrupt end this morning, because the WSPR DX Challenge web site is not functioning properly!
Thursday, 27 December 2018
Extreme QRP WSPR!
The latest package to arrive, direct from China, is this lovely QRP attenuator (200mW maximum input):
If I set the WSPRlite to its lowest output of 5 milliwatts then I can now attenuate it down to just 5 microwatts! I now just have to wait for the SMA male-male adapters to arrive in the post...
If I set the WSPRlite to its lowest output of 5 milliwatts then I can now attenuate it down to just 5 microwatts! I now just have to wait for the SMA male-male adapters to arrive in the post...
WSPR Anomaly - PY2GN
Last night was quite unusual at 14MHz, where there had been minor disturbances throughout the day. This led to the band remaining open at short skip distances into mainland Europe and even some moderate DX from the Middle East (4Z and HZ).
The single unusual spot of the night came from PY2GN at 00:20UT, with a SNR/2500Hz of -20dB. This station does feature relatively often in the unusual spots list.
Now, the distance to PY2 is over 9500km - making a consideration of the likely propagation path an interesting one! Here's the planet's situation at the relevant time:
Now, the question to ask first is: is there anything unusual about PY2GN's location that might help understand the propagation? Well, there is certainly the South Atlantic Anomaly to consider, because this is quite a significant feature of the earth's magnetic environment. This is how it looks, as measured at about 500km:
Who knows what effect this has in practice? Certainly, ionisation is enhanced in this area. Could the signal be running up the grey line to the north, being bent towards Wales by the auroral oval?
Or perhaps along the grey line to the south, again undergoing bending by the auroral oval when it gets to the north?
Or perhaps there are auroral Es drifting northwards from the southern aurora, and equivalent Es drifting south from the northern aurora, yielding a path?
Or is the path more direct, with the field of the inner Van Allen belt conveying the signal from south to north? Can a WSPR signal stay coherent under such complex paths?
Or, finally, could it be the equatorial electrojet that is responsible? This paper provides interesting food for thought.
Well, all we know for sure is that some path is allowing a coherent signal to make it to the UK. Only with a coordinated effort at both stations, to try and measure time delays, could we make some progress. Because of the infrequent nature of the event, this is not very easy to organise without particular determination at both ends.
Also interesting to note that the (northern) auroral prediction last night showed a distinct and persistent patch as far south as Spain. It's still not clear if these patches are anomalies in the model, but there certainly were plenty of short skip signals coming in from Europe all night, so the patches might well portray real auroral Es:
Looking at the southern aurora, the model again predicts quite extensive patches extending to tropical regions. This shot is a few hours earlier than the PY2 spot, but the predicted patch would be drifting over the coming hours to the right, towards Brazil.
The single unusual spot of the night came from PY2GN at 00:20UT, with a SNR/2500Hz of -20dB. This station does feature relatively often in the unusual spots list.
Now, the distance to PY2 is over 9500km - making a consideration of the likely propagation path an interesting one! Here's the planet's situation at the relevant time:
 |
| How to account for propagation at this time? Image: DX Atlas, with permission. |
Now, the question to ask first is: is there anything unusual about PY2GN's location that might help understand the propagation? Well, there is certainly the South Atlantic Anomaly to consider, because this is quite a significant feature of the earth's magnetic environment. This is how it looks, as measured at about 500km:
 |
| South Atlantic Anomaly. Image: Wikipedia/Steve Snowden/NASA |
Who knows what effect this has in practice? Certainly, ionisation is enhanced in this area. Could the signal be running up the grey line to the north, being bent towards Wales by the auroral oval?
Or perhaps along the grey line to the south, again undergoing bending by the auroral oval when it gets to the north?
Or perhaps there are auroral Es drifting northwards from the southern aurora, and equivalent Es drifting south from the northern aurora, yielding a path?
Or is the path more direct, with the field of the inner Van Allen belt conveying the signal from south to north? Can a WSPR signal stay coherent under such complex paths?
Or, finally, could it be the equatorial electrojet that is responsible? This paper provides interesting food for thought.
Well, all we know for sure is that some path is allowing a coherent signal to make it to the UK. Only with a coordinated effort at both stations, to try and measure time delays, could we make some progress. Because of the infrequent nature of the event, this is not very easy to organise without particular determination at both ends.
Also interesting to note that the (northern) auroral prediction last night showed a distinct and persistent patch as far south as Spain. It's still not clear if these patches are anomalies in the model, but there certainly were plenty of short skip signals coming in from Europe all night, so the patches might well portray real auroral Es:
 |
| Image: NOAA. |
Radio News cover art
One thing I love about blogs is the way it allows us to tell the world about our personal interests.
So I was really interested to read VE7SL's recent blog about Radio News, a magazine that ran from the early days of radio.
If you punch in 'Radio News' into a search engine, you end up spending ages being fascinated by beautiful cover art, often covering rather bizarre topics, such as the 'radio gun' (a modern version of which one might suspect, from a Ministerial statement that 'technology that would not usually be deployed') was, or was about to be, used at Gatwick airport to stop drones interrupting flights):
So I was really interested to read VE7SL's recent blog about Radio News, a magazine that ran from the early days of radio.
If you punch in 'Radio News' into a search engine, you end up spending ages being fascinated by beautiful cover art, often covering rather bizarre topics, such as the 'radio gun' (a modern version of which one might suspect, from a Ministerial statement that 'technology that would not usually be deployed') was, or was about to be, used at Gatwick airport to stop drones interrupting flights):
Wednesday, 26 December 2018
W1NEJ Anomaly - 25/26/2018
Another interesting anomalous WSPR spot came through on 14MHz overnight, this time from Eric, W1NEJ in Boca Raton, Florida. Receiver in use was the SDRPlay RSP1a.
Eric was running what is, for WSPR, a high output of 10W (40dBm), apparently into a straightforward dipole hung between palm trees. Eric's site is very near the Atlantic coast, so is obviously a good place for radio.
This is the series of spots from Eric. Notice the strong, -6dB and -9dB signals at 01:40 and 01:50UT, respectively, and the rapid weakening of the signal to undetectability over the next 40-odd minutes. Notice also how W1NEJ is the only signal heard here in the 6-hour period between 23:12UT and 05:08UT:
This is how the spots look, plotted against time (blue vertical lines are midday and midnight UT)
Locally in Wales, the Norwegian line magnetometer plots again show the field was returning to quieter conditions between 01 and 02UT, after a fairly minor disturbance at high latitudes (essentially, the daily 'ripple' of the night-time auroral oval's passage):
Looking at the graphic of the planet at 01:40UT, it's again evident that the propagation path was likely to involve ionised patches in the F2 region to cover the 3663 nautical mile distance at this time of day. Multiple hops off geomagnetically-induced E patches are also possible,but perhaps less likely. Another option is some non-great circle path, assisted by the geomagnetic field.
Also interesting to note that, after 01:28UT, I was the only station outside the US hearing W1NEJ. I have seen this with other stations, as previously noted.
Eric was running what is, for WSPR, a high output of 10W (40dBm), apparently into a straightforward dipole hung between palm trees. Eric's site is very near the Atlantic coast, so is obviously a good place for radio.
This is the series of spots from Eric. Notice the strong, -6dB and -9dB signals at 01:40 and 01:50UT, respectively, and the rapid weakening of the signal to undetectability over the next 40-odd minutes. Notice also how W1NEJ is the only signal heard here in the 6-hour period between 23:12UT and 05:08UT:
This is how the spots look, plotted against time (blue vertical lines are midday and midnight UT)
Looking at the graphic of the planet at 01:40UT, it's again evident that the propagation path was likely to involve ionised patches in the F2 region to cover the 3663 nautical mile distance at this time of day. Multiple hops off geomagnetically-induced E patches are also possible,but perhaps less likely. Another option is some non-great circle path, assisted by the geomagnetic field.
 |
| Terminator at 01:40UT, 25/12/2018. Image: DX Atlas, with permission. |
Monday, 24 December 2018
HZ1SK - midnight anomaly
Last evening (23-24/12/2018) was another very geomagnetically quiet one.
Despite this, there was a surprise appearance of numersous spots from HZ1SK around midnight, which is pretty unusual.
This is what a typical quiet day series of spots from HZ1SK very recently looks like here:
Despite this, there was a surprise appearance of numersous spots from HZ1SK around midnight, which is pretty unusual.
This is what a typical quiet day series of spots from HZ1SK very recently looks like here:
 | |
| Typical propagation day. |
After the grey line period, HZ1SK disappears into the noise, usually to reappear as one of the first-heard stations here in the morning grey line period.
Not so last night, when things looked like this:
The only disturbance to the field was again at very high latitudes, related simply to the daily changes in the quiet auroral oval. The HZ1 spots appeared at around the time of the field restoring to flat conditions, which is something I see with other anomalous spots very often:
 |
| Norwegian line stackplot. Image: Tromso Geophysical Laboratory. |
Sunday, 23 December 2018
Intreresting article.
Not very new, but very interesting article on long-path propagation:
https://www.qsl.net/ik3xtv/ARCHIVIO/QEX%20JanFeb%202017%20Article%20%20a%20study%20of%20long%20path%20echoes.pdf
https://www.qsl.net/ik3xtv/ARCHIVIO/QEX%20JanFeb%202017%20Article%20%20a%20study%20of%20long%20path%20echoes.pdf
A burst from Papa Alpha
After a nice family gathering yesterday afternoon, I decided to try some more WSPR listening with the RSP1a SDR, seeing as there was no apparent contest activity on 14MHz (yet!)
It was geomagnetically quiet, but a spectacular burst of strong signals came from the Netherlands station, PA3BTI (100mW) mid-evening, which seemed to coincide with the geomagnetic field restoring to full-quiet conditions from a small disturbance at very high latitudes; by the time we reach the Andenes station (69 degrees North), the disturbance is not really detectable.
A similar, but broader enhancement was seen from F1AGR:
It was geomagnetically quiet, but a spectacular burst of strong signals came from the Netherlands station, PA3BTI (100mW) mid-evening, which seemed to coincide with the geomagnetic field restoring to full-quiet conditions from a small disturbance at very high latitudes; by the time we reach the Andenes station (69 degrees North), the disturbance is not really detectable.
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| Norwegian line magnetometer outputs. Image: Tromso Geophysical Laboratory. |
 | ||
| Wow! +14dB SNR/2500Hz from PA3BTI (14MHz) |
Friday, 21 December 2018
WSJT-X vs. JTDX - a quick test.
Yesterday, I reported on the SDRPlay RSP1a appearing to be a very good receiver, at least as good as my FT-450 transceiver.
That result, which got me to number 5 in the DX listening challenge, was using the latest version of WSJT-X, which is meant to have 'improved' WSPR sensitivity.
At just after midnight on 20/12/2018, I changed to using JTDX for WSPR reception over another 24 hours. So that I could tell the difference, I used plain MW1CFN as the call, rather than the MW1CFN/SDR used the previous day.
Was one software better than the other?
Well, I came in at number 6 with JTDX, four spots away from being number 5. Realistically, one can say this is an inconclusive result, especially as it only covers two full 24 hour periods. Those stations in the top 10 can move around a lot from day to day, mainly according to geomagnetic conditions.
Overall, the two softwares seem to be very similar. For general antenna performance checking, use of one over the other might be of no real consequence. For more critical work, the new WSJT-X may be preferable.
The weekend is now here, together with it's massive uptick in QRM. Therfore, SDR operations are given over to VLF reception, down at around 5kHz, with a new multi-turn wire loop (about 215m total wire!) that even got my daughter excited and busy winding last night! The flexibility of SDRs is really amazing, and opens up yet another lifetime of radio interest!
That result, which got me to number 5 in the DX listening challenge, was using the latest version of WSJT-X, which is meant to have 'improved' WSPR sensitivity.
At just after midnight on 20/12/2018, I changed to using JTDX for WSPR reception over another 24 hours. So that I could tell the difference, I used plain MW1CFN as the call, rather than the MW1CFN/SDR used the previous day.
Was one software better than the other?
Well, I came in at number 6 with JTDX, four spots away from being number 5. Realistically, one can say this is an inconclusive result, especially as it only covers two full 24 hour periods. Those stations in the top 10 can move around a lot from day to day, mainly according to geomagnetic conditions.
Overall, the two softwares seem to be very similar. For general antenna performance checking, use of one over the other might be of no real consequence. For more critical work, the new WSJT-X may be preferable.
The weekend is now here, together with it's massive uptick in QRM. Therfore, SDR operations are given over to VLF reception, down at around 5kHz, with a new multi-turn wire loop (about 215m total wire!) that even got my daughter excited and busy winding last night! The flexibility of SDRs is really amazing, and opens up yet another lifetime of radio interest!
Thursday, 20 December 2018
SDRplay RSP1a - progress so far.
Well, though it remains very early days, I can confidently report that the RSP1a recently acquired here is a very worthwhile product.
My normal WSPR listening (0% transmissions) over a 24hr period with a Yaesu FT-450 transceiver usually yields a place in the top 8, depending on conditions. I can be as high as the number one receiver on occasion. This much has been reliably established over a long period of operation.
So, how does the RSP1a do? Well, first it has to demonstrate that it can cope with electric fence spikes. This is the only RFI that is present locally at the moment. The FT-450 completely eliminates this very simple, slowly-repeating spark profile with a press of the NB button, restoring clean bands across the board.
The fences are currently damaged (they need maintenance with such regularity that few horse keepers can keep up with in a windy area like this) and so tend to be off. But when they have been on, I noticed the RSP1a noise blanking functions, when using the native SDRUno software, did not remove the spikes at all.
This would render the unit rather less than useful if the NB settings could not be modified. I later learned that there are threshold limit settings for the NB functions, so once the fences come on again, I will see how they work. I would be surprised if even the simplest NB function did not work in this context.
Anyway, back to the WSPR results. The past 24 hours yielded a number 5 slot, which is pretty much where I would expect to be on a typical day with the FT-450. At £89, and provided the NB can be improved substantially, that makes the RSP1a a very good performer indeed.
During my musings on SDR, I've (re)discovered the interesting GQRX software, which seems to be quite popular, not least as it is open source. I will try that later over the Christmas period, though contests might be a problem over the holidays. Then it's a move over to the Raspberry Pi. This should be fairly easy, but one never knows with Linux-based systems, especially when the user is less than expert, like me! If I can get it all to work, then it will be straight off into a less domestic setting in my farmland-based shack, or the beach.
My normal WSPR listening (0% transmissions) over a 24hr period with a Yaesu FT-450 transceiver usually yields a place in the top 8, depending on conditions. I can be as high as the number one receiver on occasion. This much has been reliably established over a long period of operation.
So, how does the RSP1a do? Well, first it has to demonstrate that it can cope with electric fence spikes. This is the only RFI that is present locally at the moment. The FT-450 completely eliminates this very simple, slowly-repeating spark profile with a press of the NB button, restoring clean bands across the board.
The fences are currently damaged (they need maintenance with such regularity that few horse keepers can keep up with in a windy area like this) and so tend to be off. But when they have been on, I noticed the RSP1a noise blanking functions, when using the native SDRUno software, did not remove the spikes at all.
This would render the unit rather less than useful if the NB settings could not be modified. I later learned that there are threshold limit settings for the NB functions, so once the fences come on again, I will see how they work. I would be surprised if even the simplest NB function did not work in this context.
Anyway, back to the WSPR results. The past 24 hours yielded a number 5 slot, which is pretty much where I would expect to be on a typical day with the FT-450. At £89, and provided the NB can be improved substantially, that makes the RSP1a a very good performer indeed.
During my musings on SDR, I've (re)discovered the interesting GQRX software, which seems to be quite popular, not least as it is open source. I will try that later over the Christmas period, though contests might be a problem over the holidays. Then it's a move over to the Raspberry Pi. This should be fairly easy, but one never knows with Linux-based systems, especially when the user is less than expert, like me! If I can get it all to work, then it will be straight off into a less domestic setting in my farmland-based shack, or the beach.
Wednesday, 19 December 2018
Minus thirty-three.
Well, as previously noted, Joe Taylor says of WSPR:
"The protocol is effective at signal-to-noise ratios as low as –31 dB in a 2500 Hz bandwidth."
The new WSJT-X version is meant to be of 'increased sensitivity', but we aren't told how much more sensitive.
I said earlier this month that I'd seen infrequent but regular decodes as low as -33dB in the past, using older editions. I saw one again today at 18:10UT with the new edition, but they don't seem to be any more common than in the past. The next spot of WB2CPU (18:14UT) was at -28dB, so the -33dB event doesn't seem to have been down to strong adjacent signals.
"The protocol is effective at signal-to-noise ratios as low as –31 dB in a 2500 Hz bandwidth."
The new WSJT-X version is meant to be of 'increased sensitivity', but we aren't told how much more sensitive.
I said earlier this month that I'd seen infrequent but regular decodes as low as -33dB in the past, using older editions. I saw one again today at 18:10UT with the new edition, but they don't seem to be any more common than in the past. The next spot of WB2CPU (18:14UT) was at -28dB, so the -33dB event doesn't seem to have been down to strong adjacent signals.
Unusual spot - 9Z4FV
Nothing very unusual spotted last night, except for a 22:32UT spot of 9Z4FV, heard at a good -17dB SNR/2500Hz, albeit from 20W output.
Now, at 9Z4, the situation locally was one of the grey line passing away, as this plot shows:
The distance from a signal being sent from around 320km at the easternmost (night-progressing) edge of the grey line is around 3400km, which is in close agreement with the expected distance from a single F2 hop, and puts it just within line-of-sight for my station. In all likelihood, though my antenna, on near-perfect ground, has good gain to the horizon, the signal from 9Z probably came from slightly higher in the ionosphere.
Now, at 9Z4, the situation locally was one of the grey line passing away, as this plot shows:
 | |||
| Situation at 22:32UT, 18/12/2018. Image: DX Atlas, with permission. |
The distance from a signal being sent from around 320km at the easternmost (night-progressing) edge of the grey line is around 3400km, which is in close agreement with the expected distance from a single F2 hop, and puts it just within line-of-sight for my station. In all likelihood, though my antenna, on near-perfect ground, has good gain to the horizon, the signal from 9Z probably came from slightly higher in the ionosphere.
Tuesday, 18 December 2018
Solar Cycle 25: stronger than 24?
The plot below leads us nicely into a prediction by Indian researchers in Nature Communications that the next solar cycle could be somewhat stronger than the previous.
New phenomenon found?
Over the past few months, I've been quietly gathering evidence on a strange radio phenomenon I've noticed in the local area.
Regular readers will know the QTH is based on an old copper mine. This sounds fantastic - and it is - for radio. But it's dissolved iron that is probably responsible for the world beating ground characteristics to be found here, because it is by far the most common element.
Bacteria (actually, Archaea, as separate Kingdom) eat away at iron bound with sulphur, producing sulphuric acid. I've measured pH as low as 1 on the mountain. At pH of below around 5 or so, iron is in the Fe2+ state, and is dissolved (handy to know if you ever have a rust stain on the bath - just put some acid toilet cleaner on it!) At above pH 5, the iron stops being soluble, and becomes the more familiar Fe3+ in the form of a 'floc' that smothers the river bed.
So as well as having a very high level of mineralisation, there is also highly acidic conditions. Thinking about it today, I realise that sounds a bit like a battery! I must think about that a bit more.
But the strange thing I've found is that, at a very precise and repeatable location, commercial FM radio suffers 'crosstalk' for a moment. Now, crosstalk is not uncommon, and we are located relatively high up, in line-of-sight to many Irish Sea areas.
But this kind of crosstalk occurs only when I move in a car over an underground, highly acidic mine drainage stream - appropriately known as 'afon goch' (red river). The interference only happens momentarily - just a second or so, exactly as the stream passes underneath me. Afon Goch, incidentally, is the largest single source of heavy metal pollution into the Irish Sea.
It could be a coincidence, and that it's geography, rather than the river that is responsible. That's why I've been testing it many times. Stratified atmospheric conditions do not seem to be responsible, as it occurs under windy and calm weather alike, and regardless of season. And it doesn't happen anywhere else!
Well, that's something to think about some more. Perhaps the acid drainage produces some kind of earth current? Metal detectorists know very well about the crazy effects of mineralised ground which, looking at some online data this morning, tells me is due to a modified magnetic field (which is pretty obvious, really, given it's not only metal but iron in the ground).
Regular readers will know the QTH is based on an old copper mine. This sounds fantastic - and it is - for radio. But it's dissolved iron that is probably responsible for the world beating ground characteristics to be found here, because it is by far the most common element.
Bacteria (actually, Archaea, as separate Kingdom) eat away at iron bound with sulphur, producing sulphuric acid. I've measured pH as low as 1 on the mountain. At pH of below around 5 or so, iron is in the Fe2+ state, and is dissolved (handy to know if you ever have a rust stain on the bath - just put some acid toilet cleaner on it!) At above pH 5, the iron stops being soluble, and becomes the more familiar Fe3+ in the form of a 'floc' that smothers the river bed.
 |
| Afon Goch, near Amlwch. The pH remains low enough, even at 1km or so from source, to keep most of the iron in solution. |
So as well as having a very high level of mineralisation, there is also highly acidic conditions. Thinking about it today, I realise that sounds a bit like a battery! I must think about that a bit more.
But the strange thing I've found is that, at a very precise and repeatable location, commercial FM radio suffers 'crosstalk' for a moment. Now, crosstalk is not uncommon, and we are located relatively high up, in line-of-sight to many Irish Sea areas.
 |
| Acid drainage from Parys runs under the road below the white cursor (you can see vents to the surface in a line running roughly centre to upper right corner) |
But this kind of crosstalk occurs only when I move in a car over an underground, highly acidic mine drainage stream - appropriately known as 'afon goch' (red river). The interference only happens momentarily - just a second or so, exactly as the stream passes underneath me. Afon Goch, incidentally, is the largest single source of heavy metal pollution into the Irish Sea.
It could be a coincidence, and that it's geography, rather than the river that is responsible. That's why I've been testing it many times. Stratified atmospheric conditions do not seem to be responsible, as it occurs under windy and calm weather alike, and regardless of season. And it doesn't happen anywhere else!
Well, that's something to think about some more. Perhaps the acid drainage produces some kind of earth current? Metal detectorists know very well about the crazy effects of mineralised ground which, looking at some online data this morning, tells me is due to a modified magnetic field (which is pretty obvious, really, given it's not only metal but iron in the ground).
Friday, 14 December 2018
Early Xmas present arrives!
At long last, after a whole week in the post, my SDRPlay RSP1a arrived this morning!
First thing to do is laugh at the several comments on Eham reviews about the box being 'cheap plastic'. Well, both those statements are probably true, but that doesn't make it a weak or poor enclosure. It's just a circuit enclosure, with what seems to be perfectly good RF shielding (I think it has foil shielding inside, but if that's not enough for you, it's hardly difficult to add some more!)
The SDRUno software is also very easy to understand without instruction and nicely thought out. Ehammers, of course, criticise this as well!
Connection of the unit to my computer posed no problem or difficulty at all - you just plug it in and you're off straight away!
The only slight problem I had was getting the sound to route properly from Virtual Cable into WSJT-X. Also, I usually have my main rig running as CAT-controlled, so for non-CAT use (though the RSP1a can be configured to run as a CAT unit), you have to select 'none' in WSJT-X CAT control. This has worked properly only very recently, but wouldn't work at all today. Was this due to the recent WSJT-X update, or something I didn't understand?
It turns out that I had to connect the main Yaesu rig up, run WSJT-X select 'none' for CAT, then switch WSJT-X off. Then connect the SDR and start WSJT-X again. Problem solved!
On the audio side, a bit of online digging revealed a useful video that suggested once I had selected Virtual Cable as the audio input stream into SDRUno, you had to press 'Stop' on the receiver, and then 'Play' again. This solved the problem as promised.
I did notice some very big frequency drifts at the start, but these soon settled down to nice straight WSPR lines. A couple of software selections probably helped that along, too. Sensitivity and decode rate seems to be very good at the moment, as this shot of the previous 30 minutes at around 17:20UT today shows (global spots plot of those hearing FR4RX, i.e. just me and Antarctica!)
And on 30m, the RSP1a is doing similarly well this morning (30 minute slot of global VK3DQL spots, back from 09:57UT):
We'll see how well this unit brings me in on the WSPR listening challenge over coming days, though I suspect that will have to wait until any constests this weekend have fallen silent. One thought is whether the laptop, which now has to act as a fully-featured SDR receiver as well as run WSJT-X and Virtual Cable, will be caused to yield fewer decodes as a result of heavier processing demand.
First thing to do is laugh at the several comments on Eham reviews about the box being 'cheap plastic'. Well, both those statements are probably true, but that doesn't make it a weak or poor enclosure. It's just a circuit enclosure, with what seems to be perfectly good RF shielding (I think it has foil shielding inside, but if that's not enough for you, it's hardly difficult to add some more!)
 |
| My new RSP1a, with grounding clip! |
The SDRUno software is also very easy to understand without instruction and nicely thought out. Ehammers, of course, criticise this as well!
Connection of the unit to my computer posed no problem or difficulty at all - you just plug it in and you're off straight away!
The only slight problem I had was getting the sound to route properly from Virtual Cable into WSJT-X. Also, I usually have my main rig running as CAT-controlled, so for non-CAT use (though the RSP1a can be configured to run as a CAT unit), you have to select 'none' in WSJT-X CAT control. This has worked properly only very recently, but wouldn't work at all today. Was this due to the recent WSJT-X update, or something I didn't understand?
It turns out that I had to connect the main Yaesu rig up, run WSJT-X select 'none' for CAT, then switch WSJT-X off. Then connect the SDR and start WSJT-X again. Problem solved!
On the audio side, a bit of online digging revealed a useful video that suggested once I had selected Virtual Cable as the audio input stream into SDRUno, you had to press 'Stop' on the receiver, and then 'Play' again. This solved the problem as promised.
I did notice some very big frequency drifts at the start, but these soon settled down to nice straight WSPR lines. A couple of software selections probably helped that along, too. Sensitivity and decode rate seems to be very good at the moment, as this shot of the previous 30 minutes at around 17:20UT today shows (global spots plot of those hearing FR4RX, i.e. just me and Antarctica!)
And on 30m, the RSP1a is doing similarly well this morning (30 minute slot of global VK3DQL spots, back from 09:57UT):
We'll see how well this unit brings me in on the WSPR listening challenge over coming days, though I suspect that will have to wait until any constests this weekend have fallen silent. One thought is whether the laptop, which now has to act as a fully-featured SDR receiver as well as run WSJT-X and Virtual Cable, will be caused to yield fewer decodes as a result of heavier processing demand.
WSPR Listening - top slot!
Well, I'm not sure yet what part the new, possibly improved WSPR software played in this, but I managed to get to the joint top slot in yesterday's listening ranks!
This is even more remarkable, given that I was off 14MHz and on 50MHz meteor scatter (very little activity, no QSOs) for over an hour and a half last night!
This is even more remarkable, given that I was off 14MHz and on 50MHz meteor scatter (very little activity, no QSOs) for over an hour and a half last night!
Thursday, 13 December 2018
The new, 'improved' WSPR!
Yesterday, I responded to a comment by my helpful friend, PE4BAS, about his understanding that WSPR sensitivity had been improved under the latest WSJT-X general release software.
I thought Bas was mistaken, as I had read somewhere that, other than FT8 and MSK, all other modes were unchanged.
But, it seems that I was the one who was mistaken. There are a couple of references in some of the new release documentation that clearly say that WSPR sensitivity has been improved. My error, such as it was, was to believe the following within the 'Quick Start Guide':
"Operating modes other than FT8 and MSK144 are unchanged from v1.9.1"
Well, if we choose to believe it has improved, that is very welcome. I have been using JTDX for serious WSPR work for a couple of years now. It seems to me to have been better than the old versions of WSJT-X. If you could even remotely see a straight, non-aurora affected signal, then it would be decoded.
Unfortunately, I can't run side-by-side comparisons of the two softwares, so I can only go on long experience and give a subjective view. It does seem to me that the new WSJT-X might be equal to, and perhaps slightly better than JTDX, though it is far too early to draw any definite conclusions.
What is curious, though, is the claim made as follows by the WSJT-X team in the WSJT-X User Guide:
"The protocol is effective at signal-to-noise ratios as low as –31 dB in a 2500 Hz bandwidth."
Well, I've seen decodes at -31dB for years with earlier software. I'm pretty certain I've even seen a few down to -33dB, though they are not common. But -31dB is a daily occurrence. If -31dB SNR/2500Hz really is the limit of sensitivity, I was doing well in reaching it several times yesterday - and the claim of improved sensitivity might be misplaced. Either that, or the documentation has fallen out of synchronisation with the software!
One indication that WSJT-X might be better now than before is that I didn't listen for practically the whole daytime yesterday on 14MHz WSPR, yet I still ended up being number 18 in the daily listening challenge! I can usually end up in the top 4 stations if I listen for the full 24 hours and the geomagnetic field is quieter (wilder conditions then strongly favour lower latitude stations).
I hope that the arrival of my SDRPlay unit - still stuck in the chaotic Christmas post - might help, through the DX challenge, to show if the new WSJT-X reallyis a bit better, and that I can climb a little higher in the rankings!
In the meantime, this table from this lunchtime, looking back over the past few hours, suggests that, whatever the software capability, my station's doing very well - one of only three stations hearing VK4TMZ, and the one hearing him (if only just) the strongest:
Seems to be repeatable, in that I'm the only European station hearing ZS1LCD over the past hour or so:
I thought Bas was mistaken, as I had read somewhere that, other than FT8 and MSK, all other modes were unchanged.
But, it seems that I was the one who was mistaken. There are a couple of references in some of the new release documentation that clearly say that WSPR sensitivity has been improved. My error, such as it was, was to believe the following within the 'Quick Start Guide':
"Operating modes other than FT8 and MSK144 are unchanged from v1.9.1"
Well, if we choose to believe it has improved, that is very welcome. I have been using JTDX for serious WSPR work for a couple of years now. It seems to me to have been better than the old versions of WSJT-X. If you could even remotely see a straight, non-aurora affected signal, then it would be decoded.
Unfortunately, I can't run side-by-side comparisons of the two softwares, so I can only go on long experience and give a subjective view. It does seem to me that the new WSJT-X might be equal to, and perhaps slightly better than JTDX, though it is far too early to draw any definite conclusions.
What is curious, though, is the claim made as follows by the WSJT-X team in the WSJT-X User Guide:
"The protocol is effective at signal-to-noise ratios as low as –31 dB in a 2500 Hz bandwidth."
Well, I've seen decodes at -31dB for years with earlier software. I'm pretty certain I've even seen a few down to -33dB, though they are not common. But -31dB is a daily occurrence. If -31dB SNR/2500Hz really is the limit of sensitivity, I was doing well in reaching it several times yesterday - and the claim of improved sensitivity might be misplaced. Either that, or the documentation has fallen out of synchronisation with the software!
One indication that WSJT-X might be better now than before is that I didn't listen for practically the whole daytime yesterday on 14MHz WSPR, yet I still ended up being number 18 in the daily listening challenge! I can usually end up in the top 4 stations if I listen for the full 24 hours and the geomagnetic field is quieter (wilder conditions then strongly favour lower latitude stations).
I hope that the arrival of my SDRPlay unit - still stuck in the chaotic Christmas post - might help, through the DX challenge, to show if the new WSJT-X reallyis a bit better, and that I can climb a little higher in the rankings!
In the meantime, this table from this lunchtime, looking back over the past few hours, suggests that, whatever the software capability, my station's doing very well - one of only three stations hearing VK4TMZ, and the one hearing him (if only just) the strongest:
Seems to be repeatable, in that I'm the only European station hearing ZS1LCD over the past hour or so:
Wednesday, 12 December 2018
New FT8 QSOs
Well, after a bit of a strop yesterday about FT8 activity being disrupted by a new version being released by Joe Taylor and friends, I have now settled down!
I managed to install the new WSJT-X on both the laptop and Raspberry Pi 3B+ with no difficulty (other than some strange message about 'user activity', which seems to have no relevance to my operating).
As generally agreed, most people clearly haven't heard of the new release, because about 4/5 or more of FT8 signals are still old-school, and not being decoded either way.
Still, the new mode is obviously going - eventually - to become the norm, so I am sticking with it until more people make the switch.
In the meantime, I was very happy to get a call from an incredibly strong VK7BBB (sadly, another operator with no station information on QRZ.com) on 17m this morning on the new version FT8:
I managed to install the new WSJT-X on both the laptop and Raspberry Pi 3B+ with no difficulty (other than some strange message about 'user activity', which seems to have no relevance to my operating).
As generally agreed, most people clearly haven't heard of the new release, because about 4/5 or more of FT8 signals are still old-school, and not being decoded either way.
Still, the new mode is obviously going - eventually - to become the norm, so I am sticking with it until more people make the switch.
In the meantime, I was very happy to get a call from an incredibly strong VK7BBB (sadly, another operator with no station information on QRZ.com) on 17m this morning on the new version FT8:
Overnight WSPR report, 11-12/12/2018
Some moderate disturbances in the field locally early last evening, followed by a much weaker disturbance after midnight. The disturbance saw a northerly swing in the Z component, which doesn't generally produce DX spots, which indeed was the case overnight.
There was plenty of shorter-skip activity at 14MHz WSPR until around 23:30UT, and from then on, a couple of distant G stations, all courtesy of the enhanced auroral activity that took the southern limits of auroral visibility as far as Ireland and Wales. Sadly, it was completely cloudy here, so I couldn't groundtruth the forecast.
At 01:16UT, I heard OH5XO once, at -28dB SNR/2500Hz, and an SM station around 45 minutes later, followed by a series of spots of LA6GH between 03:22UT and 03:58UT, all around -26dB SNR/2500Hz. The LA spots were probably related to the restoration of the field to quieter conditions.
And that was it until advancing-dawn propagation at 06:22UT, when I heard a couple of G stations, followed very shortly thereafter by HZ1SK, presumably all coming in on very low angle paths.
 |
| Image: Tromso Geophysical Laboratory. |
 |
| Mid-evening aurora forecast extending into northern UK skies. Image: NOAA. |
There was plenty of shorter-skip activity at 14MHz WSPR until around 23:30UT, and from then on, a couple of distant G stations, all courtesy of the enhanced auroral activity that took the southern limits of auroral visibility as far as Ireland and Wales. Sadly, it was completely cloudy here, so I couldn't groundtruth the forecast.
At 01:16UT, I heard OH5XO once, at -28dB SNR/2500Hz, and an SM station around 45 minutes later, followed by a series of spots of LA6GH between 03:22UT and 03:58UT, all around -26dB SNR/2500Hz. The LA spots were probably related to the restoration of the field to quieter conditions.
And that was it until advancing-dawn propagation at 06:22UT, when I heard a couple of G stations, followed very shortly thereafter by HZ1SK, presumably all coming in on very low angle paths.
Tuesday, 11 December 2018
Reluctant advice
FT8 coding has changed. We have all been told to change to the new WSJT-X version, which is not backwards-compatible with the older versions for FT8 and MSK (so you won't see decodes from those using the old code).
New version is meant to be the global standard as of December 10, 2018. At the time of writing, only about 8% of FT8 signals on my waterfall are new code versions.
http://physics.princeton.edu/pulsar/K1JT/wsjtx.html
New version is meant to be the global standard as of December 10, 2018. At the time of writing, only about 8% of FT8 signals on my waterfall are new code versions.
http://physics.princeton.edu/pulsar/K1JT/wsjtx.html
Solar cycle forecast update: hedging in the extreme?
I'm alwaysinterested in matters relating to the solar-terrestrial environment and, like many hams, keep an active eye on how that environment is changing.
At the moment, we've reached what is almost certainly the lowest point in the trough of activity that is solar minimum. How long this minimum will last is anybody's guess.
But can anyone make a prediction on the solar cycle that is something better than a guess? I'm not sure there is.
The key point of information for most of us is NOAA. I've noticed that it is either extremely slow or reluctant (or both) to issue regular updates on how the solar cycle is going. It can be years between one forecast update and another.
OK, this is not an easy science. It is trying to grapple with a semi-chaotic and complex system that always can catch us unaware.
But let's look at what NOAA has done in recently updating its solar cycle progression pages:
Now, I remember once being a key witness in a low-level criminal Court case. The defence asked me whether it was possible the defendant did not hear me tell him he had hit a house with his lorry. After a quick mental shuffle, I replied: 'I would have to concede anything is possible, but it is unlikely'. The defence sat down, irritated.
And so it is I find these very odd forecasts. The nice red trend lines predict that solar minimum is going to continue - and see ever-lower activity - until the end of 2023! That seems preposterous to anyone following the Sun in detail. Since at least early 2017, new cycle sunspots have been clearly seen, and more have been seen since. So, like in the Court case, whilst the outcome is possible, it is unlikely.
It seems to me that NOAA are simply moving the size and position of the goalposts, yielding no useful forecast at all.
Here's my prediction: we are now in the final stage of solar minimum and, by mid-2019, we will see clear signals that the trend is upwards in activity. Without warning or explanation, at around the same time, NOAA will simply change their red trend line.
At the moment, we've reached what is almost certainly the lowest point in the trough of activity that is solar minimum. How long this minimum will last is anybody's guess.
But can anyone make a prediction on the solar cycle that is something better than a guess? I'm not sure there is.
The key point of information for most of us is NOAA. I've noticed that it is either extremely slow or reluctant (or both) to issue regular updates on how the solar cycle is going. It can be years between one forecast update and another.
OK, this is not an easy science. It is trying to grapple with a semi-chaotic and complex system that always can catch us unaware.
But let's look at what NOAA has done in recently updating its solar cycle progression pages:
Now, I remember once being a key witness in a low-level criminal Court case. The defence asked me whether it was possible the defendant did not hear me tell him he had hit a house with his lorry. After a quick mental shuffle, I replied: 'I would have to concede anything is possible, but it is unlikely'. The defence sat down, irritated.
And so it is I find these very odd forecasts. The nice red trend lines predict that solar minimum is going to continue - and see ever-lower activity - until the end of 2023! That seems preposterous to anyone following the Sun in detail. Since at least early 2017, new cycle sunspots have been clearly seen, and more have been seen since. So, like in the Court case, whilst the outcome is possible, it is unlikely.
It seems to me that NOAA are simply moving the size and position of the goalposts, yielding no useful forecast at all.
Here's my prediction: we are now in the final stage of solar minimum and, by mid-2019, we will see clear signals that the trend is upwards in activity. Without warning or explanation, at around the same time, NOAA will simply change their red trend line.
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