Tuesday, 27 December 2016

Seasonal Sporadic E

What  I like about operating on VHF is the opportunities it brings for sudden long distance contacts.

The down side of this is that you need to sit around for long periods in between bursts of activity.

This is especially true for what is sometimes called "Christmas Es". I fact it is more like "late December and early January Es", but that does not trip off the tongue so easily.

In fact it is very unpredictable, may not happen at all, and if it does come, it can arrive any time between the beginning of December and mid January. It is usually weak, short lived, but for those reasons, great fun if you happen to find it.

This year there was a sudden opening on "Boxing Day", known in many other places as St Stephen's Day, i.e. 26 December. This is close enough to Christmas to make the title just about accurate.

Most of us had been watching for a while, more in hope than expectation. In my case this involves the usual WSPR study of the 10 metre band. This is where Es springs from for me. If there is Es on 10m I look at 6m, if it is there is Es on 6m I look at 4m, and if it is on 4m I look at 2m, with each step getting less and less likely, but better in outcome if it does occur.

So on 26 December once 10m WSPR started to get very busy into the "near Continent", mostly PAs and DLs to start with, I moved up to 6m JT65.
10m WSPR activity from GM4FVM on 26/12/16. The more distant stations came at the end of the event.

6m JT65 was proving hopeless, with no takers at all. Then I noticed that Gianfranco, IU1DZZ, had posted on the WSPR.net site that 6m was open at his end. GF's posting got me thinking. Perhaps WSPR would work better than JT65 (which would happen if the signals were weak but steady). So I switched to 6m WSPR to find out.
6m WSPR activity from GM4FVM on 26/12/16.

As it became clear that 6m WSPR was well established I turned again to 6m JT65, and eventually to 4m SSB too.
4m and 6m log entry, see map below.
I was a bit surprised that this unseasonal Es lifted the MUF as high as 70MHz.

So this was a classic late Es opening. The good conditions lasted from 11:20 to 15:14 on 10m (around 165 spots), 12:00 to 13:20 on 6m (10 spots and 5 QSOs), and 12:57 to 13:29 on 4m (2 QSOs).
6m JT65 and 4m SSB activity from GM4FVM on 26/12/16
Hardly much to get excited about really, in the sense that nothing new was worked and these events do happen from time to time. But I really enjoyed the opening.

What does excite me is the unexpected nature of it all. Yes, I do get steamed up about these things.

4m was, as so often, very interesting. I worked 9A1Z fairly easily, though strong winds meant that my mast was lowered. Then I could hear GM4JJJ working some stations on CW, including what sounded like an OM or OK station, but I could not hear the other station at all. I called CQ and then, suddenly, SP6RLA popped up, worked me 5/9, and vanished. The event was over on 4m.

Es openings are always best just before they end. To work a station like SP6RLA (JO81, 1368km) out of the blue like that is typical. It combines the joy and pain of VHF working perfectly. I had thought that the 4m opening was over (wrong), but I was still calling CQ just in case. He was very strong. I heard no other SP stations, though I know other stations around me were working other stations in SP. I did not hear him working anyone else.

At times it feels as if VHF propagation provides a unique pipeline between me and the other station. It is so selective, especially as you move up the bands. By the time you reach 2 metres, where Es is fairly rare, you might just hear one station but none of the ones around that station, and nobody but you can hear him. Then the propagation moves on, and you might, or might not, hear another one.

It is this "either you work it right now, or it is gone" aspect of VHF which fascinates me. I suppose 20 metres must have similar attractions but I cannot see them.

So here I am on 27 December, with WSPR again running on 10m. Nothing is happening. In my experience of this type of Es (well, all Es really) the same thing does not often happen on successive days. But it might. You never know.

Why is there often Es activity in the depths of Winter, near the Winter Solstice? I do not know. Could it be ionisation from the Southern Hemisphere spilling over? I have never seen a satisfactory explanation.

Who cares about the explanation, it is fun to work.




Friday, 23 December 2016

WSJT-X 1.7.0

Thanks to many of you who notified me that WSJT-X 1.7.0 has now been officially launched on the WSJT website here.

This brings to an end the testing phase, when the trail versions were only available on Sourceforge.

Time to see what WSJT-X can do. I will report here on some issues I have noted so far. Some aspects like QRA64, which is an experimental mode for Earth-Moon-Earth communications, have not been tried by me yet so I will have to leave them for later.

1) Configurations
As I use different rigs for different purposes, I find this setting very useful. I have stored configurations for HF (FT450), 50MHz (IC7100), 70MHz (IC7300) and 144MHz (IC7100). Thus I can simply select the configuration and WSJT selects the rig control, sets the frequency and connects to the correct audio stream.

To make some sense of this from a ergonomic angle, I keep the HF activity to the top left of the PC display screen, 50 and 144MHz to the bottom left and 70MHz to the top right (the logbook is on the bottom right and the rotator control centre top). If I do not do this I get mightily confused (and the rigs are arranged in similar fashion on the bench).

WSJT-X 1.7.0 has a built-in solution for this, as not only does selecting the right configuration select the rig and its frequency, it also places the display in the correct part of the screen depending on which configuration I select. Now that is definitely clever. Add to that the fact that it can store the power levels by band and so forth, and that becomes a very powerful rig control tool.

2) PSK Reporter
PSK Reporter has been an option on WSJT-X as far back as v1.3.0 (and possibly further back). Whereas WSPR has its own dedicated reporting system in the excellent site WSPR.net, the other modes do not have anything similar which would allow simple "reverse beacon" operations. You can set this option and then you have to make sense of PSK Reporter, which is a bit clunky in operation.  It shows stations using various modes, including of course PSK. You can establish which mode is in use by reading the roll-over text boxes of the stations on the map.

This allows you to call CQ and then check PSK Reporter to see who has heard you. "But don't stations who hear your CQ reply to you?" I hear you say. Not likely, in my experience. I now know that I am heard by three or four times the number of stations who call me back.

And, yes of course, I pay them the same compliment by ignoring them too.

For several versions of WSJT-X we have had WSPR included.
WSPR is a low power beacon mode. In its WSJT-X guise the waterfall is much wider than the 200hz band in which WSPR stations live, so you can easily see stations who happen to be slightly mistuned.
The only possible issue I have with this version of WSPR is that the power slider allows you to carry over your power settings from other modes. You can opt to choose to carry over the settings per band, but not per mode.

WSPR is typically run using powers of less than 5 watts, often very much less than 5 watts. So a preset calibrated power attenuator for WSPR like that one that existed in WSPR 2.21 etc would be very useful, for me anyway.

This is not a big problem so long as you remember to check it, and WSPR operators are usually very careful about setting their power output carefully.

4) JT9 and JT65
As with previous versions of WSJT-X since around v.1.5.0, it is possible to run both JT9 and JT65 simultaneously, on receive at least. You have to choose which one your transmit on. This is especially useful with SDRs which allow for wide rx filter settings. The JT9 frequencies tend to be 2kHz above the JT65 ones, so with a (say) 4kHz filter you can listen to both.
You can see here that the higher rx reports, which were for JT65 stations, have a # mark, whereas the later JT9 ones are marked with a @. You need not worry too much, as if you want to reply to any of them, you just click on the station, and WSJT selects tx on either JT9 or JT65 as appropriate, moves to the correct frequency on the waterfall, inserts the callsign into the generated messages, and puts the signal report in automatically too.

If you did click on the image above to look more closely, you will see that I worked DL1FAM at a signal strength of -25dB. Now this is a figure taken against a reference figure for noise in a standard receiver using an SSB filter and it can be taken with a pinch of salt. Yes, the signal was weak, but not 25dB below my noise floor. I could also hear stations on the speaker at -10dB, but I could not hear that station at -25dB. So it was certainly weak. JT9 gives about a 2dB improvement over JT65. I would say that JT65 is a bit better than a good morse operator. So -25dB was certainly a weak signal. Not perfectly received though, as I missed one rx segment, but then QSB is always with us.

Far and away the majority of my 6m QSOs are made using JT9 or JT65, and pretty well all of my HF ones. JT65 was originally designed for use on Earth-Moon-Earth paths, but it is now firmly rooted on the HF and VHF bands for F and e-layer communication as well.

5) MSK144
This new mode offers advantages over JT6M and FSK. These include faster data rates and much better error correction. The general convention to use 15 second tx/rx segments does fox me a bit at times, but I am getting used to it. Unlike the previous modes in use, MSK144 seems at home on both the longer meteor bursts of 6m and the shorter ones on 2m.

I have reported before how I stupidly managed to get the configuration wrong somewhere along the line of setting up. I am now using RX 1500hz, F Tol 100, T/R 15 seconds. I have decode set to "deep". Deep will use more processor power than fast or normal.
The % figure in the "receiving" box indicates processor power used.

If you tick "Auto Seq" you allow the suite to complete your QSO once you initiate a contact. It will incorporate the reports and progress down through the QSO format as it receives the appropriate replies. In the absence of replies it just sends the same message (but updates the reports!). Note that the "TX Watchdog" (also a carry-over from previous versions) will eventually stop you transmitting if you fall asleep while this is working automatically.

This works well enough, save for a few niggles. If you receive more calls from a station before their report arrives, the suite keeps updating your report based on the last signal received. I have once sent five different reports before I received mine. Let us hope that the other station did not get confused. Also, some stations have sent me out-of-sequence messages, such as sending their first report as, say R-02 rather than -02, which sets the Auto Seq off course. But provided you stay in control this setting has the advantage of speeding up contacts and reducing use of the spectrum It certainly helps you get the best out of a long meteor burst.

The automatic setting for split frequency (entering a working frequency while calling CQ on a common frequency), is something I have not yet got working with the IC-7100. Nor have I used the "sh" box for shorthand messages, which I feel are not necessary for my type of operation.

6) Summary
WSJT-X 1.7.0 is another step forward.

Much has been said about MSK144, a new mode which seems by all accounts to render existing meteor scatter modes outdated. Apart from the new modes, this marks another step to incorporating all the "JT" modes into the WSJT-X wrapper. For me for instance, the "configurations" setting is a real plus. In the past people struggled to get on the air with JT6M or FSK441 using WSJT9 or 10, which did not interface well with modern rigs. Now they can use MSK144 with WSJT-X, and benefit from CAT control.

The WSJT-X suite brings us to another milestone  - the multi-band suite. Now, in theory anyway, you only need one suite to work HF, Es, E-M-E, meteor scatter, using modes such as JT9, JT65, QRA64 and MSK144. You can switch between rigs using configurations, use certain modes on certain bands or with certain rigs, and generally never actually touch a VFO or a mode control.

Ham Radio Deluxe and FLdigi may have been good HF suites, but WSJT-X is becoming spectrum-wide.

I have said it before, but it deserves saying again. If you can set up your rig audio and CAT as for, say Ham Radio Deluxe or any similar data mode, you have got exactly the right setup to run modes covering many aspects of radio activity today. The days of having several different pieces of software to run WSPR, HF data modes and meteor scatter are long gone.

Unless of course you are mad enough to run all your rigs simultaneously as I do.

But them I am a bit crazy.



Monday, 19 December 2016

It's meteor scatter time ...

I have once again been distracted by other things. Things like crimping and soldering fork connectors onto DC leads, and fixing the TV rotator.

Actually, there wasn't much to do with the TV rotator. Careful jiggling around re-engaged the gears. I took it apart and it turned out to be a superior type of TV rotator, with nice metal gears and bushed bearings, though the bearing rested on nylon-type discs. Anyway, a bearing is one thing, but when it is open on one side save for a casting on the body to hold it in place, then it is going to tilt and the gears are going to separate, if the rotator has a strong sideways force.

I guess the makers of these cheap items are not too familiar with tilt-over masts. They expect the TV antenna to be dropped into the rotator from above, rather than attached with the whole thing leaning sideways, only then to be tipped upwards to the vertical. So I suppose it is hardly surprising that after I put it on the tilting mast it jammed on being turned vertical.

Anyway, it works again in that cranky half sensible way those things do. If you do not mind having a fairly inaccurate indication of direction and keep the load light (and don't tilt it) it is fine. For portable operation in some unspecified situation yet to be defined. I have only been portable twice in my career where a rotator would have been any use, so I am not sure when this is really needed. But you never know.

No, you never know. The Perseids meteor shower in August did almost nothing here, for the second year running. So I was not sure about the Geminids in December. As it turned out things went pretty well.
 GM4FVM VHF Meteor Scatter contacts by locator squares from 1 to 18/12/16 with 500km circles.

I am a regular meteor scatter operator. This means that the showers come and go while I just plod along. Other operators turn up for a day's frenzied operations on the peak night, which gives them about 5 reasonable days operation each year. Not everybody devotes the time to it that I do, which is fair enough.

So for me, given that the peak for the Geminids this year was predicted to be 13 December, I started taking an interest on 1 December. In it for the long term, I am. 10 days of white noise beckoned. Except you never know.

Here is the table of stations worked before 13 December.
As usual click to enlarge if necessary.

The red squares are new ones.

First of all it shows that there is no need to wait for the peak day to work stations.

Secondly it shows how I can be busy only working MSK144 on 4m and 6m.

Thirdly, and sadly, it shows that JT6M is still around. Stations who worked on MSK144 during the rest of the time use JT6M for the Nordic Activity Contest on 8 December. Strange.

Fourthly, I seemed to do very well at various times of the day. Certainly, contacts are likely to be weaker and take longer away from the early morning peak, but there are still lot of people around at different times.

I have tried to encourage people to use the latest modes but it seems that they are reluctant to do it. I even tried diverting people onto the bandplan frequencies. I also tried to encourage some of them to move  away from the established calling frequencies during contests. However I have decided that this is a waste of time - they seem to need to go wherever they please and my efforts were in vain. So I will have to content myself with following the crowd.

For the 13th itself I decided to try harder to make some 2m band contacts.
Most stations on 2m were using FSK441 mode, and all the ones I worked were using this older mode.

Six new squares would always be worth the effort in my book.

Most stations send 73 to confirm the contact, some do not. I always do, and I either send 73 briefly in return to a 73 as well, or call CQ. If you do this you can be certain that you have completed the contact. If, as in one of these contacts, you get no response to your RRR message you are left high and dry. This time I claimed it.

So clearly it is worth coming on during the peak day. After that things cool down a lot. This seems to me to be a waste as there are often good contacts to be made.
In fact, there are some minor showers between the Geminids shower around 13 December and the Quadrantids during the first few days in January. These Ursids showers are weak by comparison but still useful in making a bridge between the two main peaks.

I feel that too many operators turn off their rigs between the showers and do not try during these periods. To counteract the reduced meteor action you can operate closer to the daily peak (around 06:00 local time). The only period I find it difficult to make contacts is mid-January until around the end of March.

One contact in this later group which specially pleased me was Rudi, DK7OM. We tried two days earlier, but although we exchanged reports we could not complete a QSO. I asked him for a sked and the result was a good QSO.

I have noticed that MSHV was out-performing WSJT-X on MSK144 reception. I could see and hear signals on 6m but WSJT-X was not decoding them, whereas MSHV was decoding them. In fact, the final QSO in the list with PeO, SM5EPO, was a test to see what was happening. I quickly noted that opening out the frequency tolerance on WSJT-X helped, but that also over-strained my computer processor.

Checking everything carefully I discovered that the  audio rx frequency (showing as Rx 1400 Hz) was at its default position of 1400 rather than the recommended 1500. I must have updated WSJT-X so many times over the past few months that I forgot to update that parameter this time. When I corrected it I could reduce the frequency tolerance back to 100 and still receive all the signals. Silly mistake. I wonder how many others make it too.

MSK144 is normally used, by convention, with 15 second tx/rx sectors. This is unlike FSK (30 seconds), JT65 (60 seconds) and WSPR (120 seconds). Some operators were turning up over the past few days using MSK and 30 second sectors. This still works, but it is slow, wasteful of spectrum and frustrating for other operators.

On one occasion I switched to 30 seconds to work a station. Then I saw him later still using 30 seconds and struggling to complete a QSO. So I sent him "pse change to 15sec", which he did. I then worked him again and felt that I had done us all a good job. As soon as I had finished, a German station called him on 30 seconds, he went back to 30 seconds, and that effort was wasted.

There are only certain things I can change, so the I will just have to accept the other things.

So I think that was a good meteor shower.

MSK144 is very good when it comes to working those stations who want to use it. Why it is not tested more on 2m is a mystery to me. I suppose that may be because WSJT-X is still marketed as a trial version, so some people are reluctant to try it. That's the clue in the name - trial versions are meant to be tried.

This warning every time you start it will put some people off ...
However, as I pointed out before, MSHV is available without such a warning.

Until it is launched on the official WSJT site, WSJT-X v1.7.0 will remain slightly beyond the average amateur's line of sight. Let us hope it soon progresses into general usage.

Then, hopefully, we can say goodbye to JT6M and FSK441.