Friday, 13 August 2021

A bit of meteor scatter and trans-Atlantic Es.

I have not been well.

Mrs FVM and myself headed west to enjoy a few days relaxation in far-off Kirkcudbright. We both fell ill with tummy bugs.

I have spent the last week with a bad case of what Granny Edgar would have called "The Skitters".

It got really bad at times. How bad? Doctors ask you to rate the pain in a scale from zero to ten. I cannot really do that, but it got so bad that on two occasions I looked at the radio, saw good conditions, and had to go back to bed. That is about as bad as pain can get in my book.

During long spells bent double with stomach cramp I had plenty of time to sit and consider the woes of the world (in addition to mine). I did a lot of sitting. Apart from the obvious, I found that standing resulted in falling over followed by lying down wondering what was going to happen next.

Being a normally mild mannered chap and not given to fulminating about things that annoy me, I was for once overcome with anger about aspects of my hobby. Perhaps it was the badness coming out in me.

I did write it, but I have deleted it. Sure, there are some things about this hobby which infuriate me but do I need to go on about them all here?

In summary, once anything in amateur radio becomes popular, people start attacking it. And once something becomes less popular, articles are written about how we should support this dying thing, whatever it is.

I have never encountered a hobby which spends so much time knocking the things in their interest which are growing, and blaming us all for not supporting some outdated, boring, inefficient old irrelevant aspect of it.

I will return to this I am sure.

Right, moving on for now.

The Perseids are near their peak and as usual I have been doing a bit of operating. Mostly listening I have to say, but a bit of transmitting too.

I even ventured on to 2m. I should say that I rarely do 144MHz meteor scatter these days because I find it much too much effort for very little reward. Not only have I worked so many squares over the past few years with Tropo and Es, but the QSOs are often very long and many are never completed. Still ...

144MHz meteor scatter QSOs at GM4FVM 1 to 13 August 2021

Click to enlarge images as usual.

Granny Reavey, on the other hand, used to say "Needs must when the Devil driveth". This seemed to mean that when you need to do something you may be forced to follow the path of the Devil, the Devil in this case being 2m meteor scatter.

Interesting Granny words these, "Skitters" and "Driveth"

What was driving me into the hands of the Devil here was the presence of UA2FL on 2m. I had not worked Kaliningrad on 2m before, though I did narrowly miss it once on Es (recorded somewhere in this blog). So I saw him and tried for four days before he came up into the clear and I worked him.

Working OH6HFX at 1673km is pretty satisfactory too, but UA2FL at 1470km brings the 2m country list to 42. And while I was working Slava I was called by SP2ERZ for an unusual "double", as  I worked ERZ on 4m and 2m one after the other which must be my first meteor scatter double. I did look on 6m for him but there is no MS treble here (yet).

Looking at my all-band meteor scatter list so far in this year's Perseids you can see my preference for 4m and even sometimes 6m:-

All band meteor scatter QSOs at GM4FVM 1 to 13 August 2021.

16 QSOs, 1 on 6m, 9 on 4m and 6 on 2m. How so?

Because the length of time the ionisation trails persist decreases with frequency, the pings get shorter as you go up the bands. So 2m contacts take a lot longer to complete than 4m ones, which in turn are longer than 6m (and if you go to 10m the ionisation can last so long that contacts are often mistaken for Es). 

Which makes 2m meteor scatter a bit of a pain for me (more pain Jim?).

The result is that a contact can last for an hour or more, during which time you are transmitting a signal into the unknown and waiting to see if you get a ping back to confirm that it has been received. No ping in reply does not mean that you have not been heard, indeed on 2m it often just means that you are not hearing the reply. Or vice versa ... you are rather left in the dark.

So to give an example the QSO with UA2FL went like this:-

11:37:00 I heard UA2FL calling CQ.

11:37:30 I called UA2FL

11:38:21 I received his report -02

11:38:30 I sent my report R +08

I kept sending R+08 until

11:53:02 when I heard him send RR73.

At that stage we were 16 minutes in and I had all I needed.

11:55:30  I sent him 73

I kept sending him 73 on and off until 12:50:30, which was almost an hour after I had first heard his RR73

The reason why I kept sending 73 was because during that hour, every ten minutes or so, I got his signal saying RR73, which meant that he still had not got my 73 signal. If he was still sending RR73, I felt I needed to keep sending him 73 to confirm to him that I had got his RR and that the QSO was complete. I guess he never heard my 73. I will never know unless I get a QSL card which says so. I do know he got my report and that is all I need at my end. He does not need my 73 to confirm the QSO, just to know it is complete at my end.

The thing was, as far as I was concerned the QSO WAS complete. I just had no way of telling him that, apart from sending him 73. Due to the random nature of meteor scatter he never seemed to get my 73, and he just kept going - no doubt waiting to receive it

Let us be clear about this, UA2FL was doing the right thing. I admire his patience as many other operators would just have given up and waited to see if they got a QSL card. 

Contrast this with a QSO with Ivan, S51DI, a stalwart of 4m operations. I have worked him dozens of times so no need to send my locator and save 15 seconds! :-

210812_164505    70.174 Rx MSK144   0  4.9 1553 CQ S51DI JN76
210812_164515    70.174 Tx MSK144   0  0.0 1500 S51DI GM4FVM +09
210812_164530    70.174 Rx MSK144   3  0.5 1553 GM4FVM S51DI R+08
210812_164545    70.174 Tx MSK144   0  0.0 1500 S51DI GM4FVM RR73
210812_164603    70.174 Rx MSK144  -5  2.6 1556 GM4FVM S51DI 73

Whole QSO completed in 58 seconds.

So just to put these beside each other - 2 metres took 1 hour and 13 minutes, 4 metres took 58 seconds.

The UA2FL QSO took longer than usual. OK1GU took 42 minutes to complete, still a lot longer than the 58 seconds. But 2m QSOs can sometimes take hours to compete.

The shorter and weaker 2m pings are not the only reason for this. The tx/rx period commonly used on 2m is 30 seconds, whereas on 4m and 6m it is 15 seconds. The reason for this difference is presumably rooted in the times when MSK144 was introduced to replace FSK441. FSK had a 30 second period and to avoid problems in the changeover it was decided to use 30 seconds for MSK. Yet on the other bands MSK just used a different frequency and everybody went over to 15 seconds. It used a different frequency on 2m too, so that whole argument is a bit doubtful.

I was contacted at the time by an amateur who thought that I should be campaigning for a 30 second period. I am not in the business of doing campaigns. It is not my job to tell people which period to use on 2m MSK. That is entirely up to them. They have that right, even if they are making a mistake.

There is no advantage to using 30 second periods, apart from the historic changeover period from FSK (which could have been handled differently anyway). The signal length on MSK is 72 milliseconds, so repeating it for 30 seconds makes little difference to repeating it for 15 seconds. On either system you are still transmitting for 30 seconds out of every minute. However, there is a distinct disadvantage in probability terms to using the longer period. This is due to the likelihood that the path for a signal back from a dx station being open is higher immediately after they see your signal. This is because meteor often come in showers and the ionisation will last for a certain length of time. The shorter period offers a probabilistic advantage for making shorter QSOs, or completing QSOs which would otherwise be unfinished.

The advantage extends to periods shorter than 15 seconds, and I have seen people successfully using 5 second periods. This makes the 30 second periods on 2m look a bit daft. It is true that the advantage from using shorter periods is greater at lower frequencies, but it is still a factor at 144MHz.

I have sat here and watched a full 30 second meteor burst on 2m while waiting to reply to a station - on 15 second periods I would have half the QSO completed by then.

It is not for me to try to change any of this. People have fixed ideas and each amateur is free to choose what they do. It is just a pity when they chose a standard for 2m which actually disadvantages their own efforts, when 4m and 6m can prove that there is another way. Some 4m and 6m QSOs take a long time too, but that is not self-inflicted. MS is all about probabilities and not certainties.

So I will probably continue to give 144MHz meteor scatter a wide berth.

Unless the Devil drives me toward another new DXCC.

Incidentally, the single 6m MSK QSO was to YT9A in KN04, a distance of 2003km and probably my most distant meteor scatter QSO ever. Also it was done on 100W barefoot and took only 75 seconds to complete thanks to 15 second periods...

210808_114430    50.313 Rx FT8    -12  0.2  746 CQ YT9A KN04
210808_114445    50.313 Tx FT8      0  0.0 1705 YT9A GM4FVM IO85
210808_114500    50.313 Rx FT8     -6  0.2  747 GM4FVM YT9A -12
210808_114516    50.313 Tx FT8      0  0.0 1705 YT9A GM4FVM R-06
210808_114530    50.313 Rx FT8     -4  0.2  747 GM4FVM YT9A RR73
210808_114545    50.313 Tx FT8      0  0.0 1705 YT9A GM4FVM 73

I also found time this month to work a few more stations before the Es season ends.

I managed two more in the USA on 6m (AA4DD and KK4DX). Also I stumbled across an opening into the Caribbean, and worked a new country in the shape of P41E in Aruba. HC1BI was a doubtful one, and no confirmation from Ecuador suggests that this one got away.

After a suggestion from Mike GM3PPE I signed up for Log Book of the World. I had chosen not to do this when I started using eQSL about 10 years ago. Back then I was still using a paper log book. Now as I use the excellent VQLog, I can upload to both eQSL and LoTW at the touch of a button. VQLog will also download QSL indicators from both sources, meaning that I know when a QSO has been confirmed. VQLog also uploads to ClubLog.

My first download of confirmations at LoTW was for 3300 records which had been waiting for me. I uploaded everything back for about 5 years. I may do the rest later.

Despite my hopes, HC1BI was not confirmed by LoTW.

Ah well, Ecuador is still waiting for later.

Reports on the stomach pain front have declined by 35dB. They are still not yet below the noise floor.





  1. Hello Jim, wish you and your XYL a good health and hope the pain will be over soon. I know it will affect life and even the hobby but in the end there will be another healthy time to enjoy. Well thanks for the interesting post about your MSK efforts. I did some MSK on both 6m and 4m, concentrating on 4m. I always keep KST chat on another screen since I had a number of times operators let me know that they are calling me which could be useful. Unfortunately I could not spend the time I wish to make more MS contacts. Hopefully there will be some stones left to reflect signals in the next days. I noticed that after I send "73" the opposite station does reply with "73" to finish QSO. Not always but it happens... Well, I find it amazing when you don't hear any signal and then like magic a few bursts are being decoded complete with callsign and message and then silence (noise) again. Sometimes it really takes a long time to QSO, I have to admit I do not always have that much patience... 73, Bas

  2. Bas. Thanks.
    I tried to reply before but Blogger was not working.
    I have worked some more so it did last a bit longer.
    Also, I send an extra final 73 sometimes if I think it will help. I always send 73 the first time. It would help if stations would send their locator in almost every case, but possibly not only if things are very variable. If I am pointing the right way I find that the QSO lasts longer.
    73 Jim