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12-08-20: The 2020 Perseids 144MHz Meteorscatter s2s event

They say, 100W and 10dBd were needed to successfully make MS QSOs. However, 50W and 8 dBd have been proved sufficient for a SOTA station. This is an invitation to all SOTA activators who want to do something crazy.

My report of a SOTA MS activation on 144MHz showed that there might be some SOTA OPs interested in an s2s event. One was Tom, M1EYP who asked me to organise the event on the reflector.

Except the current corona situation, the Perseids with their broad and intense maximum in mid August seem perfect. Regarding corona, it is still unclear if we all will be able to sensibly seperate ourselves for some hours on a summit of our choice then. I’m preparing for ‘yes’.
If you set up an MS station just in case and you can’t use it because there’s still a lockdown in your area , what have you lost? Nothing, you even improved your station and gained knowledge.

Event date
The 2020 Perseids will peak on the 12 August between 0800 and 2100z, according to Make More Miles 1300 - 1600z. This will be the day. According to the old MS rule of thumb that the signals in EU will be much stronger in the morning than around noon and in the afternoon, and my from experience gained feeling that a small station will rather be successful shortly before the maximum than shortly after, I alerted for 0400z. This time is rougly and may be subject to change.

Mode
I suggest MSK144 as this mode has gained much popularity and so there will be a good chance for SOTA stations to also contact non-summit stations, maybe dedicated SOTA chasers. Or is anybody fancying an old-fashioned HSCW or SSB QSO?

Basics
Experienced MS MGM OPs skip the next passages and links. Newcomers may want to watch Lyn’s, GW8JLY talk on MS.


A good introduction to operating procedures is Part 4 / chapter 1 of the IARU Region1 VHF Handbook, weak signal procedures and especially MS procedures.

Software
The most popular software is WSJT-X 2.0 or higher. If you have a running WSJT-X 144MHz SOTA setup, you’re ready to go.
I however use MSHV 2.38. It is said that this software decodes a bit more reliably than WSJT-X and can handle higher frequency offsets which is quite good for SOTA operations.

Procedures
Periods are 30s. For random contacts, central EU is 2nd period, all others 1st. For skeds, both stations agree on individual periods.
MSK144 does not use the MS report system, e.g. 37, but the SNR, e.g. 01. And it seems, there is no QSY on MSK144. All traffic takes place on 144.360. Why not, stations from the same area usually transmit during the same period and so do not interfere each other.
In the special case of a SOTA s2s event, QSY for scheduled contacts may be considered when stations that can hear each other participate in the event. I suggest to schedule contacts in this thread.

Testing
The Lyrids are still active for another two or three days, followed by the eta Aquariides up to 28 May (maximum 4/5 May). Good opportunities to test the rx setup, even at non-VHF’ish locations and with a small setup. The good thing about MSK144 signals is, you will most likely hear what you receive. If you hear the characteristic MSK sound (maybe just a ping or burst, may be a closeby staion) and see decoded message shortly after, the setup is probably ok. Best times will be early morning or late evening (EU).
Best way to test rx and tx capabilities will be a local digi station. Local contacts can be made in MSK144, no shooting stars needed.

ERP
50W and 8 dBd (1.5m boom) will be enough, quite feasible under SOTA rules. Anybody wants to try less power and become the MS QRP king? :wink:

Contest
From 11 August 1500z to 13 August 1459z, the annual MMM on VHF Dubus MS Sprint Contest will take place. All MS QSOs within the time period count, even from rovering stations. There is a QRP category < 1500W ERP which both is perfect for portable activity.

Who’s mad enough to join the event?

Ahoi
Pom

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I had plans to be in the Outer Hebrides this year for The Perseids and SOTA. SOTA by day, Perseids MS in the evening. Plan was to take the pickup and a 13ele for 2m and 5 ele for 6m with my IC706MkII giving 100W on 6m and with the old PA, 150W on 2m. I’d even arranged a generator so I could run non-QRP powers for a change. :frowning:

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I well recall a spectacular display of the Perseids during a camping holiday in 2002. It was an amazingly clear night on a very dark campsite in North-East Essex. Jimmy M0HGY and Liam were fast asleep in the tent. Me and my mate Steve were sat out drinking vodka and talking rubbish, and wondered if we’d had a little too much to drink when we both started seeing shooting stars! Lots of them, all over the sky. It was only the following day, that I noticed in the British DX Club journal I had taken as light reading material, mention of the Perseids, peaking that previous evening!

Anyway, MS is something I have never tried before in AR, so I’d really like to have a go at this. Fingers crossed that we can be out on summits by that date, and thanks to Pom @DG7ACF for organising it and providing all the interesting details. I’m going to have a read through it all now.

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I was just reminded of this excellent idea as I browsed through the upcoming alerts. I’ll add mine now. Never done MSK144 before, so really keen to have a go. Love the Perseids too, so hoping for a clear evening.

Hope other activators will join and add their alerts.

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warning - stupid question alert
I have read a number of “beginners guides to meteorscatter” on the web, and they are all very good at explaining what equipment you need, and the procedures you should follow.
None of them have explained where you should point your aerial. Is it at the meteors, or the station you want to work, or somewhere else?

thanks.
Stuart - G1ZAR

Point it where you want to work is what I used to do.

In theory, it’s even a bit off the station you want to work. In practice, this doesn’t mater for a SOTA activator, since their accuracy of azimuth is at +/- 12°, I reckon.

I can see M1EYP and OEJKL added their alerts. I’m gonna have a look at the Perseid predictions what the best times for MS will be and post them and then let’s make skeds!

Hoping for a clear sky and fb condx.

Ahoi
Pom

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Keep us informed Pom. If you decide to adjust the QRV time, I’ll copy whatever you go with.

What a great hobby this is. 19 years in and still finding completely new things to do several times every year! SOTA is a fantastic overall context to try all these different things within too.

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The Perseids are already active and so are the alpha Capricornids (max. on 29th July) [1]. This means, there will be good activity on 144 MHz MS and OPs new to MS may want to test their setup and become familiar with the procedures on 144.360 MSK144.
The Perseid’s maximum is very broad and from my experience, it’s easy to at least decode lots of MSK traffic three days in advance with a SOTA-like antenna and a shack on a balcony or in an inner city park.

However, reasonable chances to make a valid two-way QSO under SOTA rules or hopefully an s2s, will probably only be a few hours ahead of the maximum.

The maximum is expected on 12th August between 1300 and 1600 utc with a ZHR of 110 [2]. Not that bad, considering that the overall MS condx are probably best from the early morning hours until 1200 utc and the Perseids’ rates will increase until 1300z. So from the SOTA perspective, anytime before 1200z will be good. I would suggest to plan all activations accordingly.

0600 - 1200 utc would be a good time slot to arrange some skeds and try random QSOs, I reckon. So we don’t have to be QRV again at 0400 after a night of watching shooting stars, however then will be good rates. :wink:

I will be glad to make a list of skeds and add it to the first post. Not only of the s2s skeds, but any sked with a SOTA station. I don’t have to mention that all chasers are welcome to join this crazy event, do I?

I’m gonna be on DM/NS-008 from 11th August afternoon. I will be there with some lads to spend this special night on a great summit and I have permission to drive on the summit for amateur radio purposes. So we will build a base camp with tea, beer, charging facilities, and a bed on four wheels and I’m gonna operate with a SOTA compliant setup well off the base camp. To put long words short: I’ll be glad to have any sked with a SOTA OP or chaser on 11th August late evening or 12th August in the morning.
SOTA setup will be 50W / 8 dBd 6m agl with preamp. The take off is good in any direction, but best to the South and Southwest.

Ahoi
Pom

PS: Anybody fancying SSB?

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I’m having a first attempt on my summit right now. QRV on 50.280MHz MSK144 - no RX of anything yet though!

Edit: rx’d a call from Damo 2E0TXE… (doubt that was bouncing off any flying rocks though).

For some reason, WSJT wasn’t picking this up and auto-completing the QSO. Maybe it doesn’t in MSK144 mode?

Anyway, mistake #1 now corrected. I should be TXing in 2nd period for Eastbound…

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Thank you for the MSK144 QSO Tom on 6m. I was using a Hexbeam which is not the most efficient antenna on 50 MHz… yet you still gave me a +18 SNR report which surprised me. 50 watts power used from my end over a 150 Km path over the South Pennines to Cloud SP-015. I looked at the straight line of sight and the line goes within 300m of the northernmost trig point on Kinder Scout SP-001.

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©Crown copyright 2020 Ordnance Survey Media 010/20

73 Phil

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I watched the video of GW8JLY’s talk the other day. Very useful. This morning I decided to have a trial run. At 3 weeks ahead of the Perseids peak, I reckoned that 6m might be a better bet than 2m.

There were a few bits and pieces still to learn and settings to adjust. However the guys active on ON4KST were really friendly, helpful and patient. I made four inter-G QSOs on 6m MSK144, but I very much doubt any meteors were troubled to assist with those!

Via KST, DK2EA agreed to try for a QSO - and it was successful. It was clearly a MS contact too, with two sudden deluges of repeated messages from DK2EA!

I was very pleased with success on my first ever MS outing. I went onto 6m FT8 and then 2m FM to add a few more contacts.

Then over to Gun, and another couple of 2m FM QSOs.

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MS is a thoroughly reliable way of sending messages, especially using frequencies around 50MHz. So reliable that it was used by BMEWS stations in the 50s-70s as the backup to troposcatter for comms links. They used typically 1kW into 5ele Yagis using split-frequency full duplex on the links. And it keeps working after the incoming missiles have destroyed your telephone lines/exchanges which was why it was used.

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Yes continuous signals coming from The Cloud to North Yorkshire - no burst effect was evident Tom.

73 Phil

Just a comment about the Perseids being usable this early in the shower - at this time of year the sporadic meteor rate varies from three per hour in the evening to ten per hour in the morning, so at present the hourly rate of Perseids is similar to the rate for sporadic meteors. Add to this a few per hour of the alpha Capricornids and you’ll see that Perseid pings will be in the minority for now. Just looking at the hourly rates for Perseids gives a pessimistic view of what is possible.

Not my favourite mode I must say MSK144. In the last shower once I had worked a few EU stations on this mode on 6m (DL/F/PA) I didn’t see much point in continuing. More fun working Tom today for one chaser point even though the propagation was likely extended ground wave on the mode!

73 Phil

Get used to handwork again, Tom! :wink:
I’m not familiar with WSJTX as I use MSHV, but I doubt that it offers autoqso in MSK.
Anyway, you already made your first MSK SOTA QSOs. :+1:

Ahoi
Pom

Yeah Pom @DG7ACF, there were several aspects for me to learn about and familiarise with - that was the very reason I had a go on MSK144 this morning. The only aspect of the auto-QSO “missing” was the launch of the process once called by a chasing station. I had to manually select that - but then the whole QSO was handled, completed and logged by the software as normal.

I needed to adjust the FTOL setting to widen the bandwidth to 100Hz. The default setting was 20Hz and it seemed that the software was not decoding strong signals I could clearly hear.

I had forgotten about the 1st period/2nd period West/East protocol, but was reminded by reading through the WSJT MSK144 webpage on my phone while on the summit. Some time later, @g3cwi messaged me to remind me about that, but I’d fixed that issue ten minutes earlier by that stage!

It proved rather useful to be called first by Damo 2E0TXE about 2 miles away in Congleton. That QSO obviously didn’t involve any meteors! Quite a few of my other QSOs were also inter-G non-meteor affairs - but DK2EA was definitely MS. Really good that on my very first MS activation that I had obvious experience of a MS QSO on MSK144 and several non-MS QSOs on that mode - so I now know exactly what I’m looking for regards what is and what isn’t.

It is indeed early in the shower Brian @G8ADD , which is exactly why I went for the “safer” option of 6m rather than 2m - and why I went out early morning. I’ll do a few more 6m MS activations as I continue to get used to this style of operating, getting ready for the big event on the morning of the 12th.

It might not be your favourite mode Phil @G4OBK, but the point will extend your lead at the top of the G 6m Data Chaser Table!

I’m also massively looking forward to the 17m flavour in the 2020 Challenge at the start of August after working five JA stations within a half-hour spell yesterday afternoon.

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Tom,

I was in the shack so listened for you on MSK144. No decodes from you but DK2EA was filling my screen with strong and long pings, while trying to complete with you. Also saw EI, GI, SM & OH at same time.

73 Gavin
GM0GAV

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Hi Gavin

One place I never beamed was North! Next time I’m doing it, jump on KST and request a sked.

Cheers

Tom M1EYP

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