Sunday, 22 April 2018

Auroral radio images and my 2m setup.

There was an aurora here on 20 April. Rather than actually making radio contact with anyone (I heard OZ, GMs local and on Orkney, beacons in GI etc...) I decided to use my time to try to get a decent image for this blog.

For those who cannot imagine what an auroral radio signal sounds like, this blog is not going to be much use. You can find some auroral recordings on the Internet, and there are even some of GM4FVM out there.

Instead I shall try to show a beacon received via aurora on my JT65 waterfall - in this case GB3NGI the 2m beacon on the Antrim Plateau in Northern Ireland...
GB3NGI as heard via Aurora at GM4FVM on 20 April 2018, with a faint direct signal too
Here you can see the the wide traces of the beacon as it switches every minute between JT65B and its CW identification. I was pointing my antenna at 22 degrees, the azimuth angle which seemed to give the strongest AU signal at the time. Despite the beacon being at 253 degrees there is still just enough signal coming directly from the beacon to show up to the left of the auroral signal.

Note how strong the AU signal is. Also it is Doppler shifted by about 400Hz (from the direct carrier to the centre of the distortion) in this instance. This is on 144MHz; the Doppler shift and distortion are less on 70MHz and 50MHz, and on those bands SSB contacts are practical with a bit of care. Trying to have an SSB QSO on 144MHz with this going on is a struggle but certainly worth a try.

EDIT I now notice some aircraft scatter too, on the faint direct signal at 16:41. This has produced the slanted lines due to Doppler shift caused by the moving aircraft.

Then I tried to swing the beam, first pointed at the peak of the auroral signal, and then direct at the beacon:-
GB3NGI on 20 April with the beam swung from AU to direct at 16:58
You will probably need to enlarge these images by clicking on them. They will not look too good on a phone, probably better on a PC or laptop,

Anyway, the bottom 4 traces are showing the signal when I beamed North at the Aurora, and the top two when I turned the beam West to the beacon. Obviously the signal via the aurora is seriously distorted.

You can see the difference clearly on the JT65B signal which was sent during the even minutes:-
It is easy to see the modulation on the direct signal, on the auroral signal the distortion completely hides the tones. This is what makes it so difficult to use data modes, or even SSB, during an aurora. CW turns these wide signals on and off, and despite the absence of any tone, it is just about understandable. Any effective data mode might need to have on/off switching which would make it very slow compared with JT65. PI4 is a beacon mode which does work during aurora, in some circumstances anyway.

Also interesting is the effect on the CW ID coming from the beacon on the odd minutes:-
Here the wideband distortion is almost as wide as the JT65 section. However, you can see the CW callsign being sent, which causes a slight break in the wide signal. That is where auroral CW QSOs are made, by turning on and off signals which are hundreds of Hz wide.

If you have never experienced listening to an aurora you have really missed out on an amazing experience. I hope being able to see it in this way has made it easier to understand if you are not familiar with it.
I have written a long piece of drivel about my present 2m set-up.

Then I realised that I somewhere I have a drawing of what I planned, and basically the photographs should be most of what needs to be included ...
That says it all about the connections really.

TS-590 with the display showing the correct 2m frequency

This photo shows the TS-590 configured to run the transverter, with the display showing 144.429.2. The only issue with setting the tx frequency display to show directly on the 2m band is that then it only shows down to hundreds of hertz, rather than tens of hertz which is the normal resolution. As I often use data modes which give the full readout this is not much of a problem.

The significance of 144.4292 is that by convention I set the dial frequency to produce an 800hz tone on the GB3VHF beacon on 144.430000. This is easy to do as I set the beacon's steady tone to place the line directly on 800hz on the JT65B waterfall, and I must be on 144.4292. Then I juggle with the transverter offset in the 590s menu to bring the display to the correct point.

The transverter is an ME2HT-Pro2. This is capable of 60W output on 2m and I chose a 14 to 16 MHz IF.

To open the transmissions up to the full 14 to 16MHz range required to cover all of the 2m band I had to modify the TS-590 to allow it to transmit across the entire 2MHz range.

The modification is well described on the Internet. It involves removing a link ("zero ohm resistor") from one of the boards inside the radio. As this is a surface mount device it is fairly difficult to find and I asked John, G1VVU, to help me. It turns out to be fiddly, as not only is it small but you need to lever it off the board and unsolder both sides at the same time.
TS-590 - spot the link to allow transmission anywhere up to 30MHz
If you can see it there you are doing fairly well. The screw heads give some indication of scale, and they are tiny too.

Once liberated it shot off into the depths of the radio. John retrieved it under his finger nail and offered it to me so that I could keep it for later. I did not keep it as any hope of getting that back in there is lost. My eyesight is not up to it. It is minuscule - I knew that SMD devices are tiny, but I do not often have to work with them.
No, I cannot see it either.
Anyway, after that the TS-590 is free to send 1mW down the coax to my transverter, all the way from 14MHz to 16MHz.

I think that I can hear in the distance some of you saying this is a very complex road to go down just to improve on the Icom IC-7100's performance. Well, maybe, but what is the alternative? We shall have to see how the new IC-9700 works out, but transverters are still the method used by most amateurs who want to have the best chance of working weak signal traffic on VHF and UHF.




Monday, 16 April 2018

JT65, EME and the reality of Deep Search for me.

I have had to re-write this posting. I initially spent quite some time dealing with issues around the possibility of false QSOs - indeed the possibility of JT65 QSOs carried out using JT65 not being QSOs at all. The statistics of this are clear to me - JT65 with or without "Deep Search" is unlikely ever to produce any more false QSOs than may happen anyway using other modes. Sometimes mistakes are made, sometimes I get QSL requests for SSB QSOs I never made. It happens.

However, then I began to look again at SM2CEW's note and I realised that a central plank in his argument is not that DS produces doubtful QSOs but that:- "There is, therefore, a great risk that over time this will devalue the achievement of making QSO’s . Furthermore, it creates an imbalance when comparing achievements for awards, toplists or in contests." I think that maybe he doesn't like the idea that JT65 used with Deep Search challenges the efforts of those who did EME before JT65 and Deep Search came along. You will see where this changed the tack of my article.

Sorry this is so long but it is both complex and complicated.
SUMMARY: Deep Search only generates callsign suggestions, it does not generate QSOs. These callsign suggestions are occasionally wrong (false) but that does not, in my view call the entire process into question. Good operating still makes the difference.

Earth-Moon-Earth communication, "EME" (or "Moonbounce" as it is often rather inaccurately called), is bound to be on the edge of radio amateur capabilities. The path length is about three-quarters of a million kilometres, and the path loss on 144MHz is around 250dB. 99.9% of your signal is never going to reach the Moon and only about 7% of that is going to be "bounced" (scattered) back. The Moon is not a flat surface, and it moves around in space. Despite what you hear about it always having one face turned towards the Earth it wobbles, and for a lot of the time it is below the horizon. Add to that the fact that its elliptical orbit moves it closer and farther away from the Earth over time and you have a pretty tricky object to use to scatter your radio signals back to Earth.

The fact remains that EME can be done, and therefore many of us set it as a target to be achieved. For me it is not an end in itself but a level of technical efficiency to be reached, whereas for others it is an obsession to throw themselves into. Just like any aspect of amateur radio it has the potential to take over your life. This was especially so in the days before specially designed data modes, which basically means before the advent of home computers with sound cards. Before data modes EME was the preserve of the technically brilliant and the very determined amateur (i.e. not me). After data modes it became possible for modest stations to achieve EME contacts, though possibly only by taking advantage of the "super stations" with good set-ups at the other end of the QSO.
Watching a super station at GM4FVM provides hours of innocent fun (note the failed call ...)
By "modest" station I mean one like mine. I have a reasonable radio, 300W available, an antenna with a 3m boom and a rotator capable of pointing the antenna accurately at the Moon. That might be "modest" in the world of terrestrial stations, but it is positively tiny in EME terms. My station is just about the simplest setup capable of sustaining communication via the Moon, and even then I depend on a super station being at the far end. The super station would have multiple antennas, switchable polarisation, at least 1000W of power, very low loss co-ax, low noise masthead pre-amp, and antennas capable of being tilted upwards to track the Moon's elevation. I am not in that league so I am just chipping off a few contacts to find out how it can be done, and hopefully get better over time.

The difference between me making a QSO and not making one is down to fractions of a decibel.  I obviously want to have all the advantages but there is no point trying if it is not genuine. I would not want to do it if it was not valid.

This rather long ramble is meant to set the scene for a discussion of "Deep Search". Deep Search (DS) is a setting in the WSJT-X suite allowing the use of algorithms which compare partial received data with data already stored in the receiving station's computer. For example it would allow partial callsign information to be compared with a callsign stored in the computer, and then the software will make a judgement as to whether it has detected enough of the data to confirm the callsign. This has been compared to a CW operator hearing "GM4F?M", not being sure of the ? symbol and concluding that this is likely to be GM4FVM, rather than GM4FDM. I would say it is a pretty common occurrence for operators to do this, or to conclude that what sounds like a greeting of 72 is really 73, or that what sounds like a signal report of 2299 is really 599 with a dot missing.

That representation of DS, of the CW operator correcting obvious missed characters, is often quoted but it is not quite accurate. The inner workings of the decoding process for JT65 are fiendishly complex. It is not as simple as correcting a character. And here it gets a bit like self-driving cars. People are alarmed to think that a computer might make a decision which could result in a crash or loss of life. At the same time, these decisions are taken by all sorts of people every day, and many of those are not folks I would trust with my life.

I remember staring up at someone from my position prone in the gutter, having been thrown down the road after his car drove headlong into my motorbike, and him saying "I didn't see you". As the ambulance staff scraped me of off the road I might have thought that a computer controlled car might possibly not have driven into me. The point is, computers might be able to make better decisions than a human, but do we trust them? Why should I trust humans more when they keep driving into me?

I blundered into this sea of doubt during my posting here on 30 March, here. As I said, I followed W7GJ's settings, save that I used less aggressive values to save some processing power. W7GJ certainly advocates the full settings, including turning on "averaging" (building up data across listening periods) and reducing "synch" which is likely to show up as some spurious responses as well as correct ones.

Gav, GM0WDD, posed me this interesting question ...
What are your thoughts on deep search? Peter, SM2CEW, has written a thought provoking article on it.

A good question Gav and it deserves a good answer. Sadly I am not very experienced in the world of EME, but not knowing much never stopped me pontificating before.

Far be it for me to disagree with SM2CEW, who has been around EME for much longer than I have. I dare say he is right and fundamentally I agree with him if indeed the limited information which is transmitted in DS has an injurious outcome. I just have not seen any evidence that his doom-laden outcome has come to pass.

I think that SM2CEW is over-reacting.

Or rather was over-reacting, as I first read Peter's comments some years ago. He seemed to be making good points at the time. Now I have actually tried EME and set this argument against the practicalities of using the Moon, it all looks entirely different. Things have moved on in my thinking.

The issue started for me with the question of whether JT65, Deep Search and the whole thing is a con trick? This is not what Peter said, but it was what immediately mattered to me.

If indeed deep search was liable to cause lots of false contacts, using callsigns generated in the WSJT software, then presumably active EME stations would be deluged with requests for QSL cards for those contacts. If they were false contacts based on DS-generated data then the QSOs would not be in their log books and they would have to reject them. I have not heard of this deluge happening.

In fact, why isn't it happening? What is the factor stopping us all being fooled into meaningless non-QSOs with callsigns generated in our computers?

Could it be that both stations are colluding by denying the weaknesses of JT65 and DS, and confirming QSOs they know are not genuine? Maybe, but I am not so easily taken in and all it takes is a few of us to blow the whistle on something like that and down it comes.

Are we all being hoodwinked by DS? I cannot see how we could be, but I wanted to test it out.

As I understand it, only the callsigns are included in deep search. The shorthand responses are not. I am not familiar with how the shorthand responses are verified. For this purpose when I write DS I tend to mean deep search operating as part of the wider JT65 software, as I think that most people would regard any contacts in which any part has been subject to deep search as affecting the whole QSO.

Yes, DS can produce false results:-
A false decode at GM4FVM while using deep search and averaging.
This decode is obviously false. It features a callsign of a station I was trying to work the previous day on FT8. The frequency (86) is silly as EME stations tend to be evenly spaced 1kHz apart close to the 1200 mark on the waterfall. A message in that format is a reply to my CQ call and I was not calling CQ at the time. If he was calling 1210Hz lower than my tx frequency then he was pretty crazy, or more likely he does not exist. That call is simply an artifact and it is easy to see it as such.

In a funny sort of way that type of false decode is good news. It shows how unsophisticated DS's guesses really are.

At this point in my first draft I outlined what I see as a strong argument that after seeing a false posting the chances of a false QSO are tiny. Believe it or not this is a shortened version.

At random, the probability of hitting the correct sequence of responses for a QSO is one right sequence in 823,542 tried outcomes. A JT65 QSO may not look like a random situation but it is - only in the one case where the outcome is correct is there a "right" answer to a decode. All my answers to a false decode would be "wrong" and I might as well send anything, if, indeed, DS is conjuring the whole thing up in my hard drive.

If this statistic seems rather far-fetched then feel reassured that it is the same principle which stops the lottery from being easy to win, or your bank card being cloned. I doubt if this was done deliberately, but the structure around the amateur QSO sets up a format which is very difficult to fake - and just generating random replies does not work very well. So, even if DS could generate callsigns which seemed plausible, the chances of anything randomly generated hitting on the right QSO format and fooling you into thinking you had a real station are tiny.

My analysis is the sort of thing you get when an economist becomes a radio amateur.

So if random responses would not work, could DS accidentally be programmed into JT65 with the result that it produces false QSOs? In other words, can it progress down the QSO structure or does it just fire off once any time it sees something plausible? I put this to various tests. In particular I spent two days waiting for a false decode and when I got one I tried answering it to see if I could generate a false result.

Of course I did not actually transmit my reply. There is no need to as DS had generated the false call out of nowhere (actually a birdie), then could it generate a QSO? However, I still put my reply into the WSJT-X message box and pressed "Enable TX", only turning off the transmit signal path further downstream. The receive path stayed as normal, and the birdie which produced the false decode remained.

The false decode I did get is again obviously wrong, not a CQ, not a reply to my CQ call (which I did not make), so I was being a bit silly replying to it. However, in the interests of science ...
What happened when I replied to a false decode --- nothing.

20 minutes later and all my replies had gone without any response. The false QSO had no sign of arriving. It was never going to anyway because no response on the receive side is not something I had figured into my statistics. I have seen the same false decode repeat in the past and I expected that to happen again. No response (or a repeat) means that there is FAR less of a chance of a false QSO being generated than random figures would suggest. At this stage I accepted that the chances of a DS originated false QSO is likely to be no worse than human error and JT65 and DS is probably more reliable that a human.

Anyway, I am not going to do that exercise 823,542 more times only to find that a false QSO is, indeed, less likely than that. Replying to a false decode, or not replying, seems to make no difference, so there is no sign that a false QSO could ever result other than by a hugely improbable set of circumstances.

I also looked at the possibility of there being a real station calling CQ and being answered by somebody else. If I happened to call them at exactly the right time they might reply to someone else and my DS substituted my callsign for the other calling station. Once again probabilities come into this but lets just say that a similar thing could happen in any mode - I have seen it happen often in DXpeditions and contest operations where callsigns are not repeatedly used. The use of shortcuts in EME makes this type of mistake more probable, but the shortcuts came into use before JT65 was developed. This is where I find that validation from the chat room comes into its own, rather than being only a drawback as Peter seems to suggest.

If there really is no practical chance of JT65 with DS actually fooling us, beyond the odd obvious howler, then apart from making it easier for us to complete EME contacts, what is the problem?

What point is Peter trying to make in his piece? He says:-
"We appreciate that all of the historical achievements, like tropo distance records or DXCC
awards that were made using CW/SSB are indeed impossible to compare to the ones made
using digital modes, such as JT65. The fact that Deep Search QSO’s presently have the same
status as traditional modes for DXCC is something that I find totally ridiculous. The amount
of DXCC awards issued on 144 MHz have ”exploded” since the launching of Deep Search.
This is of course nice for the operators who have been wanting such an award, but they cannot
be compared to earlier achievements, using traditional modes."

Hold on. What is a "traditional mode"?

Amateurs previously used CW for EME, in most cases anyway. When it came to working CW they departed from the conventional QSO structure by dispensing with the exchange of callsigns at each over of transmission after the first exchange and adopted the shorthand exchanges "RO", "RRR" and "73". Those were sent without confirmatory callsigns and therefore you could have been receiving the replies from anybody. Are CW exchanges made with that shortcut real QSOs? To what extent is RO a signal report anyway? Does an isolated CW shortcut without a callsign attached confirm anything?

By avoiding the difficulty of having to decode CW reports like 559 the CW EME operators opened the door to challenges that their own minimising information was making EME "too easy". Therefore there is not much scope for them to blame the rest of us when things move on along the same path.

Have we gone too far with DS in further minimising the exchange of information to constitute a QSO? Surely that is a matter of opinion. In my opinion, no, we have not gone too far with DS, simply because I reckon that it use it is supported by the evidence.

I cannot see how JT65, DS, averaging and all the rest are not just further steps in making EME achievable. I am not trying to compare my achievements with people who did EME using CW. In any case, CW EME operators used shortcuts when it suited them, and the minimal information they chose as acceptable could have been said to be insufficient at the time.

This brings my mind back to the comment made by the editor of Practical Wireless who said that he hoped that the arrival FT8 did not make 6m DX so easy that it challenged his DXCC standing. Perhaps he forgets that yagi antennas made DX "easy" for him to work his DXCC entities. Or that SSB made phone contacts "easy". The whole process of developing new methods, circuits, antennas and understanding of propagation is about making contacts "easy".

Sure QSOs set up in chat rooms can open the door to too much information being exchanged over the Internet, which reduces the standing of the QSO. Could the same not have been said about skeds arranged over the phone, or via HF links, or even by post card in the good ole' days?

Over time lots of things have made awards and contests easier or harder. After World War 2 there were three entities (East Germany, West Germany and Saarland) which are now part of one entity - Germany. Did that make it harder to achieve DXCC then, but then before we also had Yugoslavia and now we have Slovenia, Croatia, Bosnia and Herzegovina, Montenegro, Macedonia, Serbia and now also Kosovo. Overall, do these things make DXCC easier or harder over time? You cannot blame deep search for all that, and frankly you cannot blame deep search for people exploiting it as a technical possibility which did not exist before either.

In my view amateur radio is for all of us, and not for the few. Perhaps these few who worked hard and gathered their status in difficult circumstances deserve to be specially recognised. I do not believe that flinging mud at JT65 is the way to increase their standing.

It goes further than that for me. By making EME possible for those with "modest" stations (albeit by piggy-backing on the lavish expenditure of the super stations), JT65 and DS is part of widening and democratising amateur radio. What else should we do? Un-invent JT65 and DS so that ancient old dozers can talk about how they had it so tough in the old days and therefore we should too?

SM2CEW has listed several issues with DS. However, he does not seem to be opposing it. He seems to be asking for the achievement of other operators to be recognised. Fair enough.

He then says:-
"But more important is to consider a better definition of what constitutes a digital QSO!
Increasingly, it appears to be be NOT about an RF radio contact, which in my view a bad
thing for our hobby. I like radio communication and I feel that our QSO’s should be made via
the radio waves. If we continue to allow the computer to decide how little information is
received and guesses what is missing, doing away with the operator, we are heading the
wrong way."

This goes too far for me. It isn't the computer which decides, it is the software which decides what to suggest. I have no problem with the software deciding that the signal level is so low that it will make a suggestion based on probabilities. As you can see, I reckon I am able to distinguish between good and bad suggestions. This is not doing away with the operator in my view.

Peter's statement ignores the rest of the QSO apart from the callsigns, it ignores that part played by QSL cards since the dawn of amateur radio to validate contacts, it ignores the shortcuts and assumptions operators were already making. It is something to hide behind if you want to avoid progress.

"If we continue to do xxx, then something will happen" is often said. But when we did continue, and this did not happen, then can we eventually accept that what we are doing is reasonable? In a particular instance, EME, we are comparing a representation of part of a callsign with a stored version of a callsign. It seems to work. Why not do it? I do not see this as part of an inevitable descent into making us Skype operators.

I agree with Peter about this:-
"It should be about skill, judgement and personal integrity."
I trust Joe Taylor on those counts. I hope I show some too.

As I often say about data modes, if you don't like them, don't do them. They are not compulsory.

It is perfectly possible to work EME with JT65 but without DS. You can turn it off.

The challenge of trying EME has prompted me to use a lot of new skills and learn new things. It has prompted me to improve my station, and not just for EME use either. If in the end I have to content myself with a lower standing than the great and the good in this hobby, then so be it. Times change. 
When Professor Higgs predicted the existence of the famous boson which is named after him I guess he thought he would never see one. Nobody has. The Higgs boson has been "proved to exist", but only by asserting that the probability of certain events occurring for any other reason was very low. Often all we have to go on is probabilities.

It seems to me that SM2CEW's fears are not justified. He is entitled to his views, and so am I. He and others are free to place their earlier achievements on a higher plane than mine. That was then and this is now. I am not in this hobby to preserve my exalted place (just as well?) so it matters naught to me.

There are issues around the exchange of real-time supporting information on chat rooms. The same comment could apply to any mode and KST. Nothing that I have seen on EME chat rooms so far devalues the contacts claimed. In fact the chat rooms seem only to confirm that the contacts reported are genuine.

Does using JT65 with DS (and averaging) robustly produce results which tally with real-time activity reported via the Internet and supported by QSL cards? I believe so.

Do the extremes of improbable QSOs suggested by using an unreliable mode actually happen with DS and JT65? For example, if DS is really predicting callsigns out of random noise and scraps of birdies, I could imagine false QSOs occurring when the Moon was below the horizon? Not in my limited experience. You might expect a false decode, but not a false QSO.

Has it fooled me too? Like the Apollo moon missions, which I now realise were faked in a gravel pit in Essex.
Ask me later to see if I am still satisfied.

So far it seems to be going fine.




Friday, 13 April 2018

SPID RAU rotator

As regular readers will know, I have replaced my ancient Yaesu G-600 rotator with a SPID RAU. Once I was changing them over they looked much the same size, but they are very different beasts.
SPID RAU (left) and Yaesu G600 (right)
The motor and gearbox area of the G600 (right) is obviously bigger, but then the motor of the SPID is outside the main case. The Yaesu has massive castings which are famous for being brittle (they may look strong but don't tighten the nuts too tightly), whereas the SPID looks carefully machined and built to last.

The decision to downgrade the Yaesu to backup status was simple. It must be well over 20 years old (I bought it second hand). The mechanical indicator in the control box had failed years ago. The direction readout on the replacement EA4TX controller was erratic and tended to move when the rotator was not turning. This looks like a fault in the sensing potentiometer inside the rotator. I need to strip it down and get inside it. I can probably get it going to use as a reserve rotator, but I doubt if it is a front line device any more. Now that I have been trying Earth-Moon-Earth I found the accuracy of this Yaesu rotator to be poor. Whether that is the same potentiometer fault or something else I cannot yet say.

Once I had decided to replace the Yaesu my preference was always for a worm gear rotator, such as a SPID or a Create. Worm gearing has an in-built braking ability. The figures speak for themselves - the SPID RAU has twice the turning torque and three times the braking torque of the Yaesu G650 (successor to my G600). Create make a very nice range of rotators but they were much more expensive than the SPID and the right model does not seem to be imported into the UK. The only Create small rotator I could find did not have computer compatibility built in, and I was not going to buy a rotator and immediately replace the controller. The SPID is cheaper than the Yaesu equivalents and technically superior, so that got my vote.

There followed some soul-searching as to whether the SPID RAU was the right model, as the larger  RAK is meatier and not so very much more expensive. This was a tough decision but finally the weight of the SPID rotators tipped the balance in more ways than one. The RAU is nearly twice the weight of the Yaesu at 5.9Kg. Whatever the merits of the larger RAK, at 8Kg it is very heavy. Too heavy in my view. Both of the SPIDs are heavier than the Yaesu, due no doubt to the use of steel rather than light aluminium castings. With a fairly light mast I am very reluctant to step up to an 8Kg rotator if I do not absolutely need one. The thing is, what do I need?

So with some helpful prompting from Bri, G0MJI, I weighed all the elements of my antenna system and concluded that the lighter RAU's specification should be fine. Ask me again after a few Scottish storms. In any case even the RAU is better able to handle the weather than the Yaesu.
Tenna Mast with SPID, 7ele 2m and 5ele 4m yagis
The difference in construction between the SPID and the Yaesu suggest an entirely different design philosophy. The SPID uses a magnetic reed switch to send direction information to the controller at one degree resolution. Supposing my antenna blows round a couple of degrees and I want to reset the controller with it using that setting (You told me that I had not tightened the nuts enough). With the SPID you just tell the controller that instead of pointing to 95 degrees you are in fact pointing to 100 degrees (or whatever). That's it. Henceforth it remembers that setting. Brilliant. Far better than the Yaesu potentiometer.

Not only does this different design philosophy apply to the direction reporting, the controller is different too. It has no moving parts, apart from the four press buttons. No gears to wear out - Yaesu please note. The digital display tells you all you need to know. The standard controller  is small enough for me to fit my FM rig control head above it in my shelving, saving space.
The standard SPID controller under the Wouxun UV950 control head
The SPID uses the controller electronics to set the stops at each end of its travel. It has the potential to turn through 180 degrees beyond the central 360 before any physical stop. I am confident that the electronic controls will stop it but you can never be entirely reliant on such things. I set the electronic stops in the controller at 20 degrees past North in each direction, which is all the margin I need. For aurora work it is good to be able to pass North for a few degrees in each direction. As it has the potential to go way beyond that I have built a bit more coax into the slack round the rotator, just in case it goes mad some day. I am being over cautious here as I expect it will never pass the electronic stops.

There are multiple operating modes in the standard controller. You can work it simply by manual operation of side to side push buttons - when you press it moves and when you release it stops. The readout gives direction in degrees. Then there is "half automatic" mode in which it works like the EA4TX controller - you keep the button pressed until the display reaches the desired angle and then after a short pause the rotator turns to that angle. This is my favourite mode if not using the computer. With the supplied controller you can have six presets too, and these can be selected using the push buttons. You can also use a specially altered mouse to select the presets - this mouse is described as "optional" although sometimes it is supplied along with the rotator. I did not get one. Fortunately GM4JJJ gave me his mouse. Thank you David.

Then there is fully automatic mode. For that you connect to a computer using a USB socket on the back of the controller. For some reason the controller has a USB A socket, so that you need a USB A to USB A cable, which is provided. Usually a device like this would have a USB B socket. Anyway, it works and the controller offers to emulate many of the major control conventions. GM4JJJ suggested to me that SPID's own format would work well with PST Rotator software and he was quite correct.

I like PST Rotator and I had already bought it for use with the EA4TX controller. It works seemlessly with the SPID - you can enter a direction by angle, click a preset or click on the on-screen compass. The SPID follows perfectly with none of the overshoot I used to get with the Yaesu. There is a lot of functionality in RST Rotator I have barely used, such as the ability to turn towards a specific DXCC, station or locator square.

You can find PST Rotator here and for 20 Euro it is a real bargain.

OK, so there are lots of good things about the SPID RAU. There are two odd things (Question, how much odder can you get than a mouse button controlled preset choice? Answer, a 4 pin "CB mike" plug and socket for the cable connection into the controller. SPID is seriously odd). Then there are two not-so-good things as well.

Odd thing 1: The instructions are a bit weird. They come on a CD and are rather hard to find. The RAU is not mentioned and you have to work out that you want to use the RAK instructions. There are instructions for things other than SPID rotators on there and it takes a bit of digging. A few good drawings would not go amiss. What drawings there are do not show the USB socket, so they appear to be a bit out of date. Someone familiar with technical writing could fix this in a day.

Odd thing 2: If you want to use the RAU in a rotator cage you need an adapter plate. On the other hand, if you are going to use it like me with a tube at the base then you do not need to buy a lower bracket. Create please note - over £100 for a lower bracket made your rotators too dear. SPID's arrangement is a bit unusual, but it suits me.

Not-so-good thing 1: The RAU comes without a power supply. You can use your 13.8 volt bench supply and in my case this would involve a 92 second wait for a 360 degree turn (the old Yaesu did it in less than 60 seconds). SPID recommend 18V (you can also use AC as the SPID controller has a full wave rectifier inside the controller). I puzzled over this until Bri, G0MJI pointed out that he had an old "Manson" bench PSU which was adjustable up to more than 16 volts. A quick check revealed that I have two of these myself, a "Sharman" and a "Mydel". Neither of them was doing anything (switch modes are more efficient!!!). I turned one up to max (17 volts, don't believe the built in meters) and the SPID turned in 72 seconds. Bri also found some 1.5mm four core mains flex from Amazon, 25m for £22.00. Great value and it produces no noticeable voltage drop - it still turns in 72 seconds. So you might already have a suitable PSU in stock, which makes this into a "Good Thing".

Not-so-good thing 2: The RAU makes electrical motor noise when it turns, especially at 50MHz and 70MHz. This is a "sparky motor contact" impulse type noise. The noise blankers on my Icom radios work reasonably well against it. It has been suggested that I try ferrites on the cable where it comes out of the motor box. This might work but the motor is very close to the 70MHz antenna so I doubt if it will have much effect. I could put my 4m antenna above my 2m one, but it is hardly going to be much better as the noise even affects my 6m antenna which is 20m away on a different mast. I guess I will have to adjust to this noise. I knew about it before I bought the SPID and it did not put me off.

On balance I like the SPID RAU. Who needs drawings and instructions when you are a radio amateur? Aren't we meant to thrive on this type of thing? Need a power supply - find one. Electrically noisy motor ... well ... that is an issue. Still, except for EME I only move my rotator occasionally and I can put up with this issue. It is accurate, extremely quiet (in acoustic terms). Backlash is zero and it functions fine with PST Rotator. £480 is not cheap, but it has a USB plug, there is no bottom bracket to buy and at £22 for the cable, the whole package was very competitive.

The SPID RAU rotator looks to me like a good design. No corporate marketing department to get their hands on it. Rugged and without bells and whistles. Down to earth design. I will see how it gets on over the years exposed to the weather and salty spray from the cliffs at nearby St Abbs Head.

So far so good.

Thanks to Bri, G0MJI, and David, GM4JJJ, for their input here. It was a struggle for me to decide which way to go, but I think we have reached the right decision at last.




Wednesday, 4 April 2018

The QSL envelope and progress to date.

The regular envelope from the QSL buro has arrived and it was bulging. In fact it was bursting out of the envelope and I must send stronger ones in future.
QSL card covering two 70MHz contacts between OH1XT ad GM4FVM
As there is nothing I will not analyse statistically, here are the votes of the Hilversum Jury (Katie Boyle died recently: she was otherwise known as Caterina Irene Elena Maria Boyle, Lady Saunders née Imperiali dei Principi di Francavilla, or just Katie Boyle to us). She was a stalwart host of the Eurovision Song Contest in the 1960s and early 70s. "Come in Ljubljana", as she used to say, and the Hilversum Jury were always suffering QRM). Ah, live TV in the 1960s. It always went wrong.

The Book: "To anyone reading this from "Far Away" (where the cows are smaller), The Eurovision Song Contest is impossible to explain. Many wise humanoids debate how the continent of Australia sometimes comes to be in Eurovision and sometimes not, how Central Asian states can be included, how it used to have relevance which it lost in 1975, how much better it was when Katie Boyle hosted it, why it matters, and even what it is. The Eurovision Song Contest brought us Abba, and little boys discovered where Hilversum was, though not why there was a jury there, and the rest is lost in the mists of time. Like RTTY, it is something ancient which has outlived its usefulness and which should be retired and forgotten about." 

51 cards arrived. One was miss-sorted and was sent back, which left 50 valid cards. Three cards each covered two contacts, making 53 contacts:-
and now the terrible figures which will point to the decline in the hobby and my part it its downfall:-
A nice split between phone (26) and machine generated (26) with CW (1) left over as being in neither category.

Of the machine generated modes, there were 5 different protocols, JT65 (14), JT9 (3), PSK (2), leaving the rest for scatter modes FSK441 (6) and MSK144 (1). Nothing at all on FT8, so either there has not been enough time for cards to arrive or FT8 operators are more likely to use eQSL.

So even with the delay in the QSL bureau system, these cards show I am dangerously near that (apparently) dreadful mantrap of using data modes most of the time. This is more evidence going back further, because we know it was happening for me in 2016.

Defence of data modes is breaking out all over. I first saw Bri, G0MJI's comments, then I sounded off myself, and now GM4JJJ has referred me to G7DDN's posting "It's not real ham radio". The doom-sayers predictions are that "this" means the end of amateur radio as we know it. "This" probably means FT8, but it is really anything which happens to be beyond their ken. These cards, covering the period 2010 to 2016, show that I was already well down the data mode path long ago. Oh dear ,what a stooshie, as they say in all the best comics.

I do not collect cards (other than putting them in the classical QSL storage facility, an old shoe box). However I do enjoy receiving them and I also enjoy replying to them. Pick of the bunch here goes to two cards from Anthonie, NL-8992. I always enjoy receiving SWL cards, and especially those from Anthonie who puts so much information on them.

Also nice are the 2 cards for FM contacts, both on 70MHz. One is from SP6MLK and the other OH1XT which dates from away back on 20 June 2010. In 2010 I was just getting going from this QTH and I only had FM on 4m with a vertical dipole at that stage.

There are nice cards too from JA2ZS and PU2NOL for 28MHz contacts, in fact those are only cards in the batch from outside Europe.

Nice too is the card from SV1BGR for our 4m contact on 22 June 2015. It may have taken almost three years to get here, but it is nice to remember that QSO. That was my first contact with Greece on 4m, and such contacts are still rare.
QSL card for GM4FVM's first 70MHz contact with Greece, with SV1BGR in 2015
Time for a quick review of progress. At this time of year I take stock and see how the last year has been. The object is to look forward to what I might do next year.

Year to 31 March 2018. total of squares and DXCC worked per band at this QTH (previous year in brackets):-

107 squares (92), 24 DXCC (19), 1 continent

204 squares (186), 39 DXCC (38), 2 continents

294 squares (241), 55 DXCC (48), 4 continents

The year to date was steady but nothing really exciting can be reported. Perhaps introducing Earth-Moon-Earth into my range of options is likely to do more for the 144MHz total in future than it has so far. Best DX was a contact with UR3EE in KN88DC, making 2727km obviously my best 2m DX to date. Ukraine was not a new DXCC as I had worked it on 2m Es in this past year, but KN88 is easily the furthest DX, beating my previous best Es distance into Belarus by 700km. This all goes to show what a large country Ukraine is viewed from compact little Scotland. The target for 2m now has to be continents rather than squares (!). Seriously, some nice Sporadic E this year would be good too.

On 4m I have still failed to work North America, though that is certainly a possibility for the next year.  Possibly more likely is Asia on 4m as Israel should become an active 4m DXCC soon. That certainly seems easier for me to work than the various Central Asian states which have 70MHz, and I know that I have been heard in Israel on 70MHz. Cyprus, maybe an easier way for me to work into a country regarded as an Asian DXCC, has not been active on 4m since the early 1980s apart from a beacon and occasional activation from the UK Sovereign Bases. No change to my 4m best DX this year - 3263km, into IL28, the Canary Islands

For 6m it all depends on multi-hop Es. The last year has had a couple of good multi-hop openings, and I worked 8 North American stations including WP4JCF again to confirm my best DX at 6733km. South America is a good 10% further, but you never know. The same distance to the East would get me to many interesting places but not so many of those have 50MHz. I want to try though.

So I had a reasonably good year last year. A lot of next year seems to involve turning the antenna East or South East.

I think that I have done all I can do to get my station into the best shape possible. Now all I have to do is sit and wait for better propagation.