Radio experiments for the Solar Eclipse on the 21st of June 2020

There is annular solar eclipse coming up on Sunday the 21st of June 2020 and the track is shown above. An annual eclipse is where the moon blocks most but not all of the light from the sun and in the centre of the path, the eclipse looks like a ring of fire.

Even though it's not a total eclipse, most of the radiation from the sun will be blocked and a group of scientists are looking for volunteers to monitor a Chinese time beacon on 10.000 MHz for any changes.

This citizen science project involves monitoring the time standard for extended periods of time using the FLDIGI software.

More info here... https://hamsci.org/june-2020-eclipse-festival-frequency-measurement

The eclipse also raises the possibility of individuals doing their own experiments. Is it possible to monitor say WSPR signals that cross the path or maybe monitoring the signal strength of a broadcast station?

It would probably involve doing some tests either side of the solar eclipse to make sure that the effects you saw were actually due to the eclipse.

The eclipse starts around 04:30 UTC and ends around 08:30 UTC. The maximum point will be over the north of India around 06:30 UTC.

Link...
1) Wikipedia link for the 2020 Solar Eclipse

Addendum...

Video about the VK9XG expedition to Christmas Island in 2018

In October of 2018, six radio amateurs from the UK activated Christmas Island which is to the south of Indonesia in the Indian Ocean. A presentation on the expedition was given at the RSGB convention in 2019 and the RSGB have now just put it up on YouTube.



I have to admit that I have pretty much no interest in these type of expeditions but I found a few points of interest in the video.

As you can see from the map below, Christmas Island is located to the south of Indonesia.

This meant that while it was easy to work areas like Japan, it was more difficult to work Europe and North America.

As you can see from the image below, they were located next to the Indian Ocean, an ideal spot for radio.

Back in October of 2018, the Solar Flux would have been very low as we were well on the way to the bottom of the sunspot cycle. This essentially meant that the higher HF bands like 10m & 12m were very poor and most of the contacts were on 21 MHz and below.

A breakdown of the modes is... SSB 11.5%, CW 68% and FT8 20.5%. This suggests that for the SSB only operator then it was going to be hard to make a contact with them.

It also reflects the explosion of interest in what was then the new FT8 digital mode and the decline in modes like RTTY.

The use of FT allowed allowed an analysis of received signal strengths.

Those with a signal to noise ratio of 0dB and above would have supported a SSB contact.
Contacts on CW would have been possible at -12dB and above.
Those contacts below -12dB were only possible on FT8.

This reflects the poor conditions and shows again that it was tough going for the SSB only operator to catch them.

It also reflects why weak signal modes like FT8 have had such an impact as it allows those with modest stations to compete with the rest.

160 Metres... It was interesting to see how they were able to work stations in the USA and how the pattern followed the areas just before sunrise.

On a more disturbing note, there were also stations on the east coast of the USA renting out time on a remote station on the west coast to make a contact on top band.

Technically it's within the rules of the ARRL DXCC programme. Morally, it's just cheating.


Links...
1) Info on ClubLog

Moonbounce on 21 MHz from the worlds largest antenna array for the band!

The 21 MHz antenna array of ES5RY in Estonia is reputed to be the largest in the world for that band.

The array is made up of eight 5-element Yagi's for 15m mounted on a 70-metre tower. It has a gain of 16dBd in free space with a beamwidth of less than 30 degrees.

It has a phasing system which allows the selection of five different take-off angles.... 4, 7, 10, 15 and 30 degrees.

Here is a video of ES5RY hearing a signal coming back from the moon on 21 MHz!



This next video shows the construction of the array...

Amazing 5600 km opening on 144 MHz from Cape Verde Islands to Poland

This post is now in two parts.

The original post is shown in Part 1 below.

The updated information with the log from D4VHF is shown in Part 2 further down the post.

* * * * *

Part 1...

On Friday the 29th of May 2020, there was an extensive Sporadic-E opening across Europe which reached as high as 144 MHz allowing stations across the continent to make many fine contacts.

The most extraordinary contacts however was probably the opening from the Cape Verde Islands off the coast of Africa to Poland on 144 MHz. The longest path recorded seems to have been when the FT8 signals from D4VHF were heard by SP5XMU in Warsaw, a distance of just over 5,600kms.

The map above shows the stations on FT8 that reported hearing or were heard by D4VHF. The most intensive part of the Sporadic-E seems to have been along a narrow corridor stretching from Lyon in France to Warsaw in Poland.

Mode of Propagation... It seems very likely that there were two propagation modes at work for this extraordinary path from the Cape Verde Islands to Central Europe.

As shown by the tropo prediction map above courtesy of F5LEN, there is a reasonably stable maritime tropo duct from the Cape Verde Islands to south coast of Portugal, a distance of about 2,800kms.

The path from Poland to the south-west of the Iberian Peninsula was spanned by a Sporadic-E opening which was in progress across Europe at the time.

As with openings of this nature, there is always the possibility of double hop Sporadic-E which can't be discounted for a good part of the path. However, this tropo duct off the north-west coast of Africa is a remarkably steady feature and it seems to be there for a large part of the year. It's hard to imagine that it didn't play a major part in the opening.

FT8 screenshot from D4VHF

In 2019, there were other similar mixed Sporadic-E & tropo duct openings from Cape Verde to Italy and Germany. The distances involved with this opening to Poland though are exceptional.

* * * * *

PART 2...

Update. Now that the dust has settled, we can look at the log of D4VHF and who they worked...

While many stations heard D4VHF on FT8, a much smaller number managed to make a contact.

Here is the log...

2020-05-29,10:05:15, CT1END,IM58,144.175900,FT8,-07,-04,,,
2020-05-29,11:10:00, IK4ADE,JN54,144.175900,FT8,-07,-09,,,
2020-05-29,11:57:15, IK0ZYH,JN62,144.175900,FT8,-15,-17,,,
2020-05-29,12:15:45, EA8AJC,IL18,144.175900,FT8,+28,+17,,,
2020-05-29,12:36:00, F6EAS,,144.175900,FT8,+04,+02,,,
2020-05-29,12:43:30, EC1KV,,144.175900,FT8,-15,-15,,,
2020-05-29,12:49:15, F1DUZ,IN97,144.175900,FT8,-18,-19,,,
2020-05-29,12:52:00, F6CIS,,144.175900,FT8,-15,-19,,,
2020-05-29,12:59:45, F6DBI,IN88,144.175900,FT8,-03,-07,,,
2020-05-29,13:22:30, F8DBF,IN78,144.175900,FT8,-06,-08,,,
2020-05-29,13:47:00, G4RRA,,144.175900,FT8,-15,-16,,,
2020-05-29,13:49:00, G8BCG,,144.175900,FT8,+00,-16,,,
2020-05-29,13:52:00, GW7SMV,,144.175900,FT8,-05,-16,,,
2020-05-29,13:54:30, G3NJV,IO70,144.175900,FT8,-15,-01,,,
2020-05-29,13:55:30, G7RAU,IN79,144.175900,FT8,-13,-13,,,
2020-05-29,14:19:15, CT1IUA,IM67,144.175900,FT8,-16,-12,,,
2020-05-29,15:27:00, DJ8RZ,JN58,144.175900,FT8,-08,-10,,,
2020-05-29,15:30:45, DL5MCG,,144.175900,FT8,-09,-19,,,
2020-05-29,15:34:45, I2FAK,JN45,144.175900,FT8,+10,-11,,,
2020-05-29,18:41:15, CT1ANO,IN51,144.175900,FT8,-18,-19,,,
2020-05-29,18:55:15, CU2GI,HM77,144.175900,FT8,-19,-18,,,
2020-05-30,08:39:45, EA8AIN,IL18,144.175900,FT8,-09,+08,,,
2020-05-30,16:21:30, EA7FDW,IM76,144.175900,FT8,-11,-12,,,
2020-05-30,16:44:45, EA7E,IM66,144.175900,FT8,-18,-20,,,
2020-05-30,16:49:45, CT1EYQ,IM58,144.175900,FT8,-18,-17,,,
2020-05-30,17:16:45, EC2AGL,IN91,144.175900,FT8,-06,-16,,,
2020-05-30,17:22:45, CT1ADT,IM57,144.175900,FT8,-13,-07,,,

The FT8 signals sent and received by D4VHF according to the PSK Reporter website are shown at the end of this post.

Some points...

1) SSB V FT8... For a Sporadic-E opening on 144 MHz, a mode like SSB would be much better in terms of speed. However, look at the signal strengths in the log. Most are in the minus dB range so a SSB QSO would probably have not been possible.

As for what would be a better mode is up for debate. Marginal contacts via CW? Faster digital modes like FT4? No matter what mode was used, there would have always been incomplete contacts and a limit to how many would get in the log.

2) Mode of Propagation... From what we know, there seems to be two components.

First, there is a marine duct off the west coast of Morocco which allows VHF signals to propagate from Cape Verde Islands up to the Canary Islands (1500kms), Portugal & Spain (3000kms) and the UK (4000kms).

According to one of the operators of D4VHF...Mark EA8FF, there was no tropo between D4 and EA8 or EA7 at the time. And yet, this marine duct over the sea was probably present for a good part of the path. I don't think we can discount it and yet, there must surely be Sporadic-E openings on 144 MHz in that part of the world as well? We can't always assume it's a marine duct.

While we can debate the paths from D4 to the coasts of Portugal or the south of Spain, those signals from further north were almost certainly via Sporadic-E.

The question is was it tropo & Sp-E, multi-hop Sp-E at 144 MHz?? Just in terms of probability, I personally don't believe in triple hop Sporadic-E at 144 MHz. Double maybe, triple?!?!

3) Sporadic-E to the UK... The problem with just a list of stations is that there are like data points for a graph, they don't make much sense until you draw the graph. In the same vein, when you generate a map and see the location of the stations, you can see patterns.

Again, see the map above. Note how the UK stations are strung out in a nice narrow line. This is a classic Sporadic-E footprint. The furthest station was GW7SMV at just over 4300kms.

4) Poland... The other unusual dimension to this opening was the unusual opening at the same time from Portugal to Poland. See the QSO map below from Tom, SP5MXU...

As you can see, SP5XMU was able to work stations in Portugal at a distance of almost 2800kms. What is unusual about this is that the usual maximum distance for one-hop Sporadic-E is about 2300kms. Where did the extra 500kms come from?

This is usually explained by say a tropo extension at one or both ends. Another is the possibility of chordal hop as suggested by SO3Z in the comments. In that scenario, the signal is going between two Sporadic-E clouds before returning to the ground again.

The chordal hop theory may help explain how the 144 MHz signals covered at least part of the 5600km distance from Cape Verde Islands to Poland.

Part 2 Conclusion... In the past with traditional modes like SSB and CW, we could be reasonably sure about the mode of propagation on VHF bands like 2 metres. Now with digital modes like FT8 we are seeing signals buried in the noise which makes it harder to be certain about how the signal was propagated.

I know FT8 isn't popular with everyone but the new digital modes are allowing radio amateurs to discover paths on VHF that we never knew existed.

* * * * *

Equivalent Distances... As always, it's interesting to look at some maps to put these remarkable distances in perspective.

The 5600 km distance from the Cape Verde Islands to Warsaw would reach as far north as Oslo, the capital of Norway.

It's hard to believe but the whole island of Iceland is actually closer!

From a western perspective, the equivalent distance reaches as far as Washington DC in the USA.

Remember, there are no satellites or moonbounce involved here. This is a 144 MHz signal being propagated by Sporadic-E and tropo.

What if...??? The map of the USA above suggests maybe one potential extraordinary path. From time to time, there seems to be a tropo duct across the Atlantic from Care Verde to the the Caribbean. Could this be extended even further to the west by a Sporadic-E opening at the same time???

FT8 signals heard by D4VHF...(over 3400kms)

QRSS reception reports on 28 MHz - Fri 29th May 2020

Friday the 29th of May 2020 was an extraordinary day with widespread Sporadic-E across Europe. While the various VHF bands up to 144 MHz were open, I spent some time listening for QRSS signals (very slow visual morse code) on 28 MHz.

To put the European stations heard in context, first see the map with distances below...

a) First Grab... The short skip on 28 MHz started early and I heard the usual stations near London, roughly 650kms.

M0BMN is a lot further west and as he is just 430kms away, I had trouble getting a good trace of his QRSS signal.

b) Doppler... This is another screen grab later on. Note the double trace on some of the signals.

Pay special note to the signal from G0FTD. On the left, it's weak but clear. On the right, there are two distinct signals from him. The upper trace is steady and is almost as if that signal is coming from a stationary Sporadic-E cloud. The lower trace starts to diverge more over time as if it that signal was coming from something moving at speed and creating doppler shift.

I suspect it was coming from a Sporadic-E cloud that was in motion and half-ways through the second trace, it either reached a point or ionization level that it no longer supported propagation.

The other theory might be that it was aircraft scatter although I still prefer the moving Sp-E cloud theory.

c) Iceland... There was also some good Sporadic-E conditions to the north and I got a screen grab from TF3HZ in Iceland for the first. time.

I also noted a signal up higher in the band but I'm unsure who it is? The amount of Frequency Shift Keying (FSK) seems to be lower than the rest.

(Update: The mystery signal is LB3AH in Oslo, Norway).

d) TF3HZ & M0GBZ clashing... In this screen grab, note the signal from TF3HZ. At first, he is in the clear and on his own. Then the short skip to the east improves and I note that TF3HZ in Iceland and M0GBZ near London are actually on the same frequency.

On a band where there are just 10 or so Hertz between stations, it's easy to end up on the same frequency as someone else especially if they are from a different area.

(Update: The mystery signal at the top is probably an image of G0FTD. The mystery signal at 620 Hz is LB3AH in Norway)

As this second grab shows, they were clashing for quite a while as the conditions were excellent.

e) M0GBZ in the clear again... In this grab, you can see how on the left, TF3HZ in Iceland and M0GBZ to the north of London are still clashing. I then lose the path to Iceland and the signal from M0GBZ becomes clear again.

f) Trans-Atlantic... VE1VDM... All of the QRSS signals from Europe are via one-hop Sporadic-E. To cross the Atlantic, the signal needs several Sporadic-E hops.

As I'm on the north-west edge of Europe, I'm within two Sporadic-E hops of Vernon, VE1VDM in Nova Scotia in Canada.

I first noticed VE1VDM's signal on WSPR on 28.1246 MHz and he transmits a QRSS signal as well just below it. He sends the letters VDM and the weak signal is shown below...

Vernon also transmits a QRSS signal on 28.0008 MHz where the European stations are...

And that mysterious signal again?!?

During another grab, there was a brief opening to G6NHU near London and I could see that VE1VDM was almost on the same frequency.

Towards the bottom of the screen, there is a very faint record of the signal from OK1FCX in the Czech Republic. He sends a signal that has three levels so it can be easy to identify even if the signal is too weak to decode.

In conclusion... Another good day for QRSS signals on 28 MHz and it's interesting to note the way signals change over time. As noted in a previous post, I believe QRSS is the only mode where you can actually see the propagation changing visually.

At this stage, I'm running out of new stations to catch! I think I have seen most of the European stations at this stage.

Links...
1) Report from MW1CFN for 28 MHz QRSS signals heard in NW Wales on the same day.

WSPR problems at 28 MHz...

WSPR - Weak Signal Propagation Reporter. I have been monitoring the WSPR frequency on 28 MHz recently as the conditions have been really good and there are now a good number of stations mostly from the northern half of Europe transmitting on the band.

There are a few important issues that you must be aware of when you transmit a signal on WSPR.

1. Timing... Regardless of the band, your time on your PC must be spot on. I've seen examples where people are transmitting tens of seconds too late!  This is an example of people just letting their WSPR transmitters on without checking if it is working ok.

WSPR transmission outside the two minute window marked by the Green lines

2. Frequency... On the lower bands like say 80m or 40m, transmitters drift a lot less. On 10m, the frequency accuracy and drift becomes a bigger issue.

This is an example from the WSJT-X waterfall of someone way off frequency....

This WSPR frequency on 10 metres is 28.1246 MHz and the band is just 200 Hz wide i.e. audio frequencies of 1400 to 1600 Hz.

As you can see from the screenshot above, someone was about 230 Hz too low and no-one is ever going to decode them.

3) Drift... For the two minute WSPR transmission, the signal shouldn't drift by more than 4 Hz.

This image above shows the frequency of the WSPR signals plotted against time. The signals in the top half of the image show normal WSPR signals which are two minutes in duration. As can be seen, they are nice and straight.

In the lower part of the image, there is an example of a drifting WSPR signal. Over the two minutes, it drifts in the region of 15 Hz, way too much to be ever decoded.

If you're on WSPR on 28 MHz and you're not being heard then look at your time, frequency and drift.

Digital radio for the Marine VHF Band???

I find it interesting to follow how digital radio is gradually replacing its analogue counterparts.

The Electronics Communications Committee (ECC) of CEPT recently released an article outlining how digital radio could be introduced to the Marine VHF bands.

At present, the allocated frequencies are in the frequency band 156.025 MHz to 162.025 MHz and are mostly FM i.e. analogue.

The channel spacing is 25 kHz which means that there is a lot of spectrum on the band not being used and there is the potential to squeeze a lot more channels in.

In the article, it states that "with the exception of the automatic identification system (AIS) on channels AIS1 (161.975 MHz) and AIS2 (162.025 MHz) and digital selective calling (DSC), currently all the remaining listed channels are used for analogue voice communication. With the digital data exchange allocations in future, some channels will be used for data transfer and not for voice communication any longer. New digital radios need to be developed, which is different equipment than the current voice communication radios. As the result, the frequencies in the VHF maritime mobile band will be shared by four different systems: analogue voice telephony, DSC, AIS and digital data exchange."

There is a huge legacy issue though to overcome first. For a business, they can just swap out the gear and radios when they upgrade from FM to digital. With the Marine VHF band, there is a huge decentralised user base that will take years to change over.

The article suggests the use of DMR (dPMR) as introduced in recent years on the amateur bands..."The technical candidate solution is dPMR (digital Private Mobile Radio) – a technology currently used in land mobile communications as a replacement for analogue FM voice communication in both VHF and UHF bands. dPMR has been standardised by ETSI, the European standards organisation."

The article suggests that initially, the new digital channels which take up 6.25 KHz and these would fit between the existing analogue FM channels as shown below on the left.

Eventually the FM channels would be phased out and be replaced with all digital (above right). The end result would be a doubling of the number of channels on the Marine band.

It not hard to imagine perhaps a transition period where dual mode (FM & DMR) radios would exist and then there would have to be a date whereby everyone would need to changed over to digital.

In tests done in Estonia, they reported..."Participants in the test were generally positive about the introduction of digital communication with the range being the same (or better) than the range for analogue communication. At the maximum distances, the digital communication remained understandable (d = 19,6 NM) while the analogue communication experienced very high noise and was not understandable."

In the tests done in the Netherlands, they reported..."The users and the observers found the digital voice quality the same or better than the analogue one. The users reported back that listening to digital voice with noise reduction made it easier and less intensive to listen. The users concluded that the digital transmission of voice enabled the same functionality of operation of the ship as for an analogue radio system."

Full article... http://apps.cept.org/eccnews/may-2020/index.html

First trans-Atlantic QRSS signal of 2020 on 28 MHz - Mon 25th May 2020

Monday 25th May 2020. For a change, I left the radio on the WSPR frequency of 28.1246 MHz this morning to see what could I hear. At the time, there seemed to be some unusual propagation in that I was hearing Iceland to the north-west.

Then I got two decodes of the WSPR signal from Vernon, VE1VDM in Nova Scotia, Canada!

Timestamp          Call MHz SNR Drift Grid Pwr Reporter RGrid km az
 2020-05-25 11:30 VE1VDM 28.126118  -24 -2 FN85ij 2 EI7GL  IO51tu  4001 59 
 2020-05-25 11:20 VE1VDM 28.126118 -22 -1 FN85ij 2 EI7GL  IO51tu 4001 59 

While 28.0008 MHz is the usual QRSS frequency on 10 metres, some stations transmit right next to the WSPR frequency of 28.1246 MHz so that receive stations can listen for both WSPR and QRSS signals without changing frequency.

It just so happened that I had the SpectrumLab audio analyzer programme running as I often use it to check the frequency of beacons on 28 MHz. When I looked, I could see the QRSS signal (very slow morse) from VE1VDM but it was slightly drawn out as I was using the 'QRSS 1' option. I switched to QRSS 3 and the screen grab is shown above.

I suspect the signal from Vernon may have been at its best when I was hearing the WSPR signals. I'd guess that the QRSS signal used to generate the plot shown above is certainly not stronger than the -22dB or -24dB WSPR signal.

VE1VDM was using a QRP Labs U3S and 5 watt PA combo sending 4 watts into a full size Windom hung as an inverted V at about 30' AGL at apex, I was using a vertical half-wave for 28 MHz about 4 metres above ground level.

Mode of Propagation???... How did this QRSS signal cross the North Atlantic?

A few days ago, VE1VDM had been heard on WSPR in Luxembourg and Germany, a distance of about 5000 kms. This was most probably triple hop Sporadic-E... i.e. 1700kms x 3 hops. The second hop signal that day was probably landing somewhere in the ocean about 600kms to the west of Ireland.

For the trans-Atlantic opening today, I think I was hearing VE1VDM via double hop Sporadic-E i.e. 2 x 2000km hops. It's likely that the signal may have reached only Ireland and the western part of the UK as that's close to the limit for two hops on 28 MHz.

For more information on QRSS activities, there is an active group HERE

4000km+ path from the UK to Cape Verde opens up on 144 MHz - May 2020

Monday 25th May 2020. It looks as if the maritime tropo duct from the UK to Cape Verde Islands off the west coast of Africa is open again.

The 144 MHz reports are shown below...

Wednesday 27th May 2020...
It looks as if the path to the UK may have been disrupted but it looks as if there was a Sporadic-E opening allowing stations in France and the N of Spain to access the marine duct to the west of Morocco.

Tuesday 26th May 2020...
D4VHF G4LOH 2m FT8 4098 km 08:47:14
M0AFJ D4VHF 2m FT8 4094 km 07:41:26
D4VHF G3NJV 2m FT8 4090 km 01:03:14
D4VHF G7RAU 2m FT8 4086 km 08:24:14
D4VHF GW4SHF 2m FT8 4404 km 01:00:14
D4VHF EI3KD 2m FT8 4170 km 00:24:14

Monday 25th May 2020...
Txmtr Rcvr Band Mode Distance Time (UTC)
GW4VXE D4VHF 2m FT8 4280 km 16:25:27
D4VHF GW0KZG 2m FT8 4276 km 20:56:11
D4VHF GW1JFV 2m FT8 4264 km 22:34:41
D4VHF EI8IQ 2m FT8 4256 km 19:50:14
D4VHF GW6TEO 2m FT8 4249 km 14:44:14
D4VHF EI8KN 2m FT8 4230 km 15:01:11
G0FUV D4VHF 2m FT8 4209 km 20:47:57
MW1CFN D4VHF 2m FT8 4438 km 17:35:56
GB5VEP D4VHF 2m FT8 4438 km 15:21:56
D4VHF G4ELI 2m FT8 4101 km 15:54:14
D4VHF G4LOH 2m FT8 4098 km 07:19:14
D4VHF G3NJV 2m FT8 4090 km 07:18:14
M0AFJ D4VHF 2m FT8 4094 km 07:13:56
D4VHF G7RAU 2m FT8 4086 km 07:09:14
D4VHF GW4SHF 2m FT8 4404 km 04:55:14
G4LOH D4VHF 2m FT8 4098 km 00:01:27

Sun 24th May 2020...
G7RAU D4VHF 2m FT8 4086 km 23:35:26

As you can see, the distances involved are in excess of 4,000kms which is always incredible  when you consider that it's 144 MHz.

The tropo forecast is for a reasonably stable path from Cape Verde up to the Bay of Biscay but the last few hundred kms may be a problem.

Check out the website of Pascal F5LEN for the tropo forecast.... http://tropo.f5len.org/atlantic-ocean/atlantic-d4-ei/

Trans-Atlantic opening to the USA on 28 MHz - Sat 23rd May 2020

Saturday 23rd May 2020. The 28 MHz band was pretty much open all day with strong signals from all over Europe. I noticed some trans-Atlantic signals late in the evening so I left the radio monitoring the FT8 frequency overnight.

This was the first real multi-hop opening to the USA so far in 2020. The distances in the USA were from 4380 kms to 6370 kms so  think this was probably 3 hop Sporadic-E.

At this time of year, I use FT8 pretty much as a propagation tool. I listen for a while to upload reports to the PSKReporter website and I then check who I have heard in the last 15 minutes. If things get unusual then I start tuning around.

WSPR... When I noticed the FT8 signals were getting very strong, I left the radio on the WSPR frequency. As you can see from the map, there was plenty of short skip on the band in the range of 500 to 1000 kms. i.e. UK, Belgium, N France and the Netherlands.

What I find interesting about WSPR are those signals from stations running less than 100 milliwatts...

Timestamp Call MHz SNR Drift Grid Pwr Reporter RGrid km az # Spots
2020-05-23 17:14 G4KPX 28.126027 -17 0 JO02dj 0.005 EI7GL IO51tu 594 268 1 decode
2020-05-23 17:06 DL0PBS 28.125990 -8  0 JO33 0.05 EI7GL IO51tu 1048 266 4 
2020-05-23 16:36 F4HON 28.126005 -20 0 JN19ij 0.01 EI7GL IO51tu 827 294 2 decodes
2020-05-23 16:26 PD0KT 28.126030 -15 0 JO33le 0.01 EI7GL IO51tu 1046 268  12 decodes
2020-05-23 16:16 ON4LUK 28.126192 -20 -1 JO11 0.05 EI7GL IO51tu 782 277 3 
2020-05-23 15:30 DF4PV 28.126078 -18 -1 JN49ax 0.05 EI7GL IO51tu 1167 287 17 
2020-05-23 12:58 LA1G 28.126045 -21 0 JO49ub 0.02 EI7GL IO51tu 1387 243 7 
2020-05-23 12:56 OZ1IPH 28.126089 -8 0 JO47xi 0.02 EI7GL IO51tu 1324 250 4 
2020-05-23 12:56 OZ2M 28.125996 -15 0 JO65fr 0.02 EI7GL IO51tu 1428 261 4 

As you can see from the edited heard list above, two were running as little as 10 milliwatts and G4KPX has just 5 milliwatts!

QRSS... I had a listen for some QRSS signals from the UK when I was getting started hearing WSPR signals from there...

As outlined in a previous post, most of the UK stations are around London which is about 700kms from here.

The mystery signal 'CDJ' turned out to be Patrick ON4CDJ in Belgium, a distance of about 900 kms. It should be easy to get a proper decode in the future.

I also noticed hints of a very wavy QRSS signal above G0FTD. I think it's probably M0BMN in the west of England. As he is in IO82WN at a distance of about 430 kms, it is very short for Sporadic-E on 28 MHz and will probably take an exceptional opening to get a good signal.

World First FT8 Moonbounce contact completed on 432 MHz...

One of the niche areas of amateur radio and perhaps one of the most difficult is trying to make contacts by bouncing radio signals off the moon. 'Moonbounce' or EME (Earth-Moon-Earth) has its proponents who squeeze every last bit of improvement out of their antennas and equipment to overcomes the huge losses involved.

On a posting on the Moon-Net, Joe Taylor K1JT said he believed that the first moonbounce contact had taken place with the FT8 digital mode.

On the 21st of May 2020, an EME contact on 432 MHz had taken place between W2HRO in New Jersey and PA2V in the Netherlands.

While the weak signal FT8 mode is hugely popular on the HF and VHF bands, modes like JT65 are more popular for EME due to its better sensitivity.

Here is the posting from K1JT....

Some here will be interested to learn that earlier (21May20) today W2HRO and PA2V easily made (as far as I know) the first EME QSO using the FT8 mode.

Paul and Peter used WSJT-X 2.2.0-rc1, a beta-release candidate for version 2.2 of the program WSJT-X. Both stations have moderate 4-yagi setups on 432. Conditions today were not particularly good: degradation around 3 dB, and the Sun only 20 degrees from the Moon.

For terrestrial use the FT8 decoder searches over the range -2.5 to +2.4s for clock offset DT between transmitting and receiving stations. When "Decode after EME delay" is checked on the WSJT-X "Settings" screen, the accessible DT range becomes -0.5 to +4.4 s. Just right for EME.

FT8 uses 8-GFSK modulation with tones separated by 6.25 Hz. At the time of this QSO the expected Doppler spread on the W2HRO - PA2V EME path was 8 Hz, which causes some additional loss of sensitivity. Nevertheless, as you'll see in screenshots posted here, the copy was solid in both directions:

Why might you want to use FT8 instead of "Old Reliable JT65" for EME QSOs? FT8 is about 4 dB less sensitive than JT65, but with 15-second T/R sequences it's four times faster and it doesn't use Deep Search.

When I was active in EME contests on 144 MHz, I was always frustrated that even with reasonably strong (for EME) signals, one's maximum JT65 QSO rate is about 12 per hour. With FT8 you can do 40 per hour, as long as workable stations are available.

What about FT8 EME on 1296 MHz? It might sometimes work, but Doppler spread will probably make standard FT8 a problem. But if there were sufficient interest, we could make an "FT8B" or "FT8C" with wider tone spacing.

Please try FT8 for EME on any of the bands 144, 432, and 1296 MHz, and let us know your results.

-- 73, Joe, K1JT

For the FT8 moonbouce contact on 432 MHz, W2HRO was running 1KW into 4 x 15 el Yagis. PA2V was running 1KW into 4 x 27 el Yagis.

QRSS Signals from the UK on 28 MHz - Tues 19th May 2020

QRSS is a mode where a morse code signal is sent very slowly so that it can seen on a screen rather than heard by ear. This allows signals that can be up 20dB below the noise level to be seen.

While it might seem outdated by some of the more modern digital modes like WSPR or FT8, what is really interesting about QRSS is that you can visually see the propagation moving around.

On Tuesday the 19th of May 2020, there was really intense Sporadic-E on 28 MHz with a very short skip opening from Ireland to the UK. This allowed me to hear the QRSS signals from stations near London as shown on the map below....

The key points here before we look at the QRSS plots are...

a) G6NHU, G0MBA & G0PKT are all very close to each other and about 650 kms from my location.

b) G0FTD is about as far but is 50 kms to the south of the cluster of three.

c) M0GBZ is along the same path as the group of three but is about 90 kms closer at 560 kms.

d) The shorter the distance then the smaller the Sporadic-E footprint tends to get.

As shown above, it tends to be long and narrow and this will be shown in the QRSS examples below.

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Screen grab 1.....

In this image above, you can see all of the signals. G0FTD has two transmitters and is the weakest.

***

Screen grab 2...

In this image, the Sporadic-E footprint moves north and even though G0FTD is just 50 kms from the more northern stations, he moves outside the footprint.

The cluster of three remain remain the same while M0GBZ disappears as the skip lengthens for a while before coming back.

* * *

Screen grab 3...

In this plot, the Sporadic-E skip distance increases and M0GBZ disappears. G0FTD disappears for about two minutes before the footprint moves south again.

On the right hand side, all of the QRSS signals are there but they now become quite fuzzy which may indicate multipath. Perhaps the Sporadic-E has broken up into several clouds rather than maybe the single one before.

In conclusion..... This was the my first reception this year of the UK QRSS stations on 28 MHz and as you can see from what's written above, the plots show a lot.

From what I now, the QRSS mode is the only one where you can actually see on a screen how the propagation is moving around in real time.

Listen on 28.0008 MHz on CW for these stations running just a few hundred milliwatts.

276km Reception of Beacon in Wales on 28 MHz

During a Sporadic-E opening on the 20th of May 2020, I came across GW7HDS/B beacon in the south of Wales on 28.2215 MHz.

This is a very unusual beacon for me as it is 276 kms away and would normally be too far away for tropo and too close for Sporadic-E. When I heard it first, I thought it must have been some exceptionally short Sporadic-E.

I noticed however that the signal was pretty constant. After a few hours, it was still there and didn't behave like Sporadic-E.

By accident, I also noticed that the BBC Radio 4 signal on 104.9 MHz from Haverfordwest on the west coast of Wales was a big signal here. Even though it is some 140 kms distant, I was able to listen to it using just my mobile phone and the headset lead as an antenna.

Later in the evening, the GW7HDS beacon had gone and coincidentally, so had the signal on 104.9 MHz.

I often hear stations on the west coast of Wales on 10m on FT8 but it's hard to read any meaning into signals that are there in bursts and are infrequent. Are they tropo? Aircraft scatter? Back scatter?

Tropo conditions on the higher VHF bands like 2-metres and 70-cms are pretty common but not so much on the lower bands like 10-metres. Was it a tropo signal on 28 MHz? Possibly but I still suspect it might have been backscatter for Sporadic-E.

With the beacon frequency stored safely in a memory channel on the radio, I'll have to look out for it again in the future.