Friday, 21 December 2018

The etiquette of a meteor scatter contact

I have a couple of postings nearly ready so this one should be quickly followed by another. Nevertheless, there are some things I want to get on record before we move on. These are about how we make meteor scatter QSOs, not about the data mode technology or the science of the meteors themselves.

First of all though, as it is nearly Christmas, I have to clear up some doubts amongst you all about what to buy me for a present. It is customary to give some manly scent at this time of year, but the one I use is not available in most shops because it is, of course, a designer label. Not for me (the man who has everything) something common to the parfumiers of Paris. No, coming in a subtle plain grey tin, is my "Co-op for Men". It will only cost you £1.00 for a 250ml spray, available via the exclusive Co-operative Wholesale Society of Manchester (branches all over the UK). Do I have sophisticated tastes, or what? Plain postage will do, no need to send it "signed for".'

Moving swiftly on, I know that some beginners on MSK144 and meteor scatter are flummoxed by the strange way contacts are carried out. It is not easy to know where to beam. Also, the long gaps in the QSO when nothing appears to be happening can be confusing.

As for beam angle, WSJT-X's meteor scatter solution, MSK144, offers two suggested beam directions when you put in a callsign and locator. These are "Az", the true direction, and "B", which is a suggested direction (sometimes B is called a "Hot bearing", which I thought was when the wheels fell off your Morris Minor). In theory the true direction will not work at all. Beaming directly at the station should produce no result as the meteor trail will block the direct path. In practice this is not quite true, but there are still better results to be had by beaming slightly off the true angle.

The angle WSJT-X suggests will provide a path to one side, and the relative deviation suggested to the other station should have you both pointing to the optimum point in the sky for communication. The reality is that my beams are not very gainy so they are wider than perhaps the designers of WSJT expect. So for me, a smaller correction seems to suit better. I generally take the true angle and add some correction up to about half that suggested. However, I always correct on the same side of the true as the "B" angle suggests so that we both point on the correct side of the true path.

Note that the deviation suggested will depend on the distance to be worked. So the two stations I worked along the same true beam heading in my last post, the Drammen Radio Society, LA2D, in JO59 (522km) suggested a deviation of 14 degrees north of true (Az54, B40), while Jukka, OH6UW in KP22 (1742km) had a suggested deviation of only 10 degrees north (Az54, B44). Other factors come in, but generally the further away the smaller the deviation. The less directional you antenna is, the less this matters. For a short yagi you can pretty well forget about it.

The other oddity for someone trying MSK for the first time are the rather un-nerving silent gaps between decodes. Because the meteors are often sporadic, you might transmit for 5 or 10 minutes before the station at the other end hears you. This is understandable (not everybody is as good an operator as you) but then there might be another 5 or 10 minutes before you hear their reply. So there is a variable wait to get the reply, during which you do not know whether to  keep sending, give up and try to work somebody else, go and have a cup of tea and a fig roll, or abandon meteor scatter entirely. My advice is to keep sending for as long as you can without overheating your equipment.

How difficult this can become depends on whether you are operating during a strong meteor shower or looking for "random" meteors at any other time of the year. During a major shower things work like an FT8 contact, you get the reply immediately and every signal is long and  strong so you feel comfortable. But when the shower slackens off you have long gaps of unpredictable duration. This adds to a joyous period of expectation during the quiet periods.

Take yesterday ... I heard that German stations had now got access to 4m again. So I went to 70.174 to call CQ. I heard from DK2EA and we exchanged reports. I never heard his RRR and the next decode I got from him was him working  G0CHE. At the same time OH3XF in KP10 called me. At this stage I do not know if DK2EA has received my report. He may have replied or not, I may have missed his reply, and he has gone on to work G0CHE. As clearly he now is doing something else, I decided to turn my beam to OH3XF instead.

After exchanging reports with OH3XF I heard him sending 73. At this stage many stop, but I decided to sent 73 three times to show OH3XF that I have heard him. In theory this could go on for ever, as not hearing anything might mean that OH3XF has stopped, or just that the meteors are not falling at this right moments and he is still trying to send me 73. There is no positive way to know.

After that, having sent 73 three times I went back to DK2EA and tried to finish that QSO (which might be finished anyway). I then received DK2EA sending CQ twice, but he did not reply - or I din't hear him reply.
GM4FVM trying to work DK2EA but succeeding with OH3XF
Frustrating? I do not know for sure that I worked DK2EA, but the fact that he did not come back to me later suggests that I did.  I did work OH3XF, (KP10, 1575km), a nice bit of DX. He replied to my CQ, and it took me about 5 minutes for me to get that reply, during which time I had started a QSO with another station. This is not unusual. You then have to decide which one to work (or try both, as some stations do, sending messages alternately). Most people just go for the best DX.

So it can get confusing. This variable 5 to 10 minute gap can mean that it is 20 minutes before you get a reply to your call, during which time you are feeling a bit on edge. The better the DX, the longer you are likely to wait. Some random contacts can last for hours if you have the patience, but the message is not to give up.

During all the time I was working OH3XF I could easily have received a further message from DK2EA (I didn't, which suggests he was beaming somewhere else by then). Anyone can call you at any time, they having heard your CQ of 30 minutes ago. This requires you to be flexible and ready for anything.

The QSO with OH3XF was quite quick at 4 minutes 15 seconds after I heard him, but I do not know which of my CQs he was replying to. Depending on which one of 18 CQs sent by me over  a period of 9 minutes, it was a total of 9 minutes or 18 minutes or probably somewhere in between.

For comparison, I had a QSO with DF5VAE, Charly, (JO64, 1004km) on 2m on 12 December. I saw a CQ from him and replied and the whole QSO took 18 minutes and 30 seconds. I waited 12 minutes and 30 seconds between hearing his report and receiving his confirmation that he had got mine, during which time I was sending him my report every 15 seconds. Charly emailed me with a very nice message - it turned out that he had called me after an earlier decode but it had only been one way at that time. You just never know ...

Remember, if you hear someone replying to your CQ of 30 minutes ago then they have been calling you for 30 minutes, i.e. 60 times. They must want to work you!

Despite all this complication, during meteor showers most QSOs are fairly quick and easy. It is only nutters like me who love random CQs who plod on for hours flogging lost causes. Many times I have sent a report and waited ages for a reply, even sometimes seeing the DX station working someone else in the meantime. I hope that when they do eventually see my message they will reply to it - and they usually do. If we have exchanged reports they can feel free to work somebody else while I send RRR, provided of course they reply to me once they do eventually get my signal. And persistence often works.

I say I like random meteor scatter, working outside the showers. I also like random QSOs, not involving skeds. Sure, I can do individual skeds and I welcome anyone who want to set one up. What I do not do is use chat rooms to organise my QSOs. There is one, KST Chat, which many use. I do not use KST. I find that people use it to avoid listening on the bands. Sure there are good folks (don't write in to say you are one of these good ones) who use it to advance their activity. Many others simply use KST to avoid having to listen and thus avoid doing the work of an amateur. They prefer to chat about irrelevancies and repel all newcomers to KST. It isn't what I want to do, but they can do what they please. It is a free world, or at least it is supposed to be a free world.

I find that those who claim this to be a free world, or a free country, often use the expression to avoid responsibility. With the privilege of an amateur radio licence comes some responsibility to other amateurs. It helps to actually listen to the radio. If your head is up your rear end on a chat room you don't hear very much (unless you do it with headphones on of course).

I just do not like chat rooms. Now we have network radio for setting up skeds, and that seems like a nice radio-alike way of doing it. Chat rooms seem to take the amateur's attention away from the radio and into the world of Narnia. But fine, off you go, nobody is stopping you. Just do not write to me to complain because I do not like KST. It doesn't mean I do not love you as a person, it means I do not use chat rooms.

OK, meteor scatter is daunting for the beginner. I cannot deny that long and worrying silences, strange beam headings, odd spells of heavy activity with weeks of seemingly nothing, uncertainly about who you are working and if you are finished, a distinct lack of 73s, plus lots more, seems to be a long list of off-putting peculiarities. However, it is very rewarding. Just imagine sending a signal and waiting in hope for ten minutes for a reply, which might come right now or later. Then ages later, out of the blue, some DX appears. Delayed gratification - just what we hair shirts love.

On the 6 metre band, at least, you can operate for a lot of time as if you are on a "conventional" mode.

Finally, it helps to set up a separate WSTJ-X "configuration" for MSK with longer watchdog times and so forth, and I hope to cover that at some stage too.

Speak soon (I'm usually on Echolink).




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