Tuesday, December 27, 2022

Long Path Propagation on the 17m HF band - Dec 2022

Larry, VO1FOG in Newfoundland, Canada has been carrying out a number of long path propagation experiments on the HF bands recently and I found this one especially interesting. For the purpose of clarity, I'll try to give an overview of what happened so people will understand what is in the video clip further down this post.


VO1FOG is located at the eastern side of Newfoundland, Canada and on Wednesday the 21st of December 2022, he was listening to the daily morse code practice transmissions on 18.0975 MHz from W1AW in Newington, Connecticut. 

The distance from VO1FOG to W1AW at the ARRL headquarters is about 1,660kms and the direct short path signal was quite strong. However, VO1FOG was also hearing W1AW via the long path which means it nearly has to go completely around the globe. The long path is around 38,420kms.

VO1FOG was using a 3-element SteppIR antenna at 23-metres above ground level. 


The advantage of this type of antenna is that the lengths of the elements can be lengthened and shortened by motors rather than having to rotate the whole beam. This means that VO1FOG can switch from short path to long path in about six seconds.

The image below shows some morse code signals from W1AW via short path.


The dots and dashes are nice and clean and the word 'SAID' can be clearly seen.

The image below shows some morse received via the long path.


It's not the same word but you can see that it's a lot more messy with the dots and dashes coming from the short path signal mixing in with the dots and dashes coming from the long path.

The audio of the W1AW signal can be heard below. Remember that there is nothing wrong with the signal, you're just listening to the same signal arriving in Newfoundland at different times.

VO1FOG reports that the test was done at 14:50 UTC. The approximate propagation conditions for W1AW's location on 17m is shown below.


It's interesting that the long path isn't too far from the Grey Line path which is near where the sun is setting or rising.

Larry has carried out several tests like this recently and he reports that he hears both long path and short path almost daily about an hour either side of his local solar noon.

He has seen this echo effect on the 20m, 17m, 15m and 12 m bands and to a lesser extent on 10m. He did tests with K5WLT in Texas who was using 400w into an 80m dipole and the echo was seen on multiple bands on multiple days.

Larry usually does his tests by getting the other station to send the letter 'E' i.e. one-dot with a space after it. The image below shows the test with G0OVK in England when a second dot can be clearly seen.


Analysis... With the rising solar flux, a lot of people are probably hearing strange echoes on SSB and CW signals and not realise what it is. It obviously helps if the transmitting station is running high power as the long path has to travel almost around the world.

When Larry sent me the information and as I was preparing this post, I couldn't help but wonder if the signal from W1AW went around the globe for a second time? If the path is open and the signal goes around the world, does it keep going round and round the globe getting weaker and weaker each time it passes?

Is it possible to hear the second echo as the signal passes for the second time? Is it strong enough?

What about the time signal WWV on 15.000 MHz and 20.000 MHz? That produces a tick once a second, it should be possible to hear the long path tick as well. Again, is it possible to hear more than one echo in the space between ticks?

It's intriguing to think that there may be signals from high power transmitters going around the globe multiple times before finally dying out when the propagation conditions change. Again, it raises more questions... how long? Up to a second? Several seconds? Minutes? That's leads then to the subject of 'Long Delayed Echoes' which is another topic in itself.

If you have a good beam or antenna for the HF bands then have a listen and see what you can hear.

Thanks to Larry, VO1FOG for all of the background information for this post.

Saturday, December 24, 2022

PJ4MM in the Caribbean gets permit for 40 MHz & 70 MHz - Dec 2022


Martin, PJ4MM on Bonaire in the Caribbean reports that he has just received an experimental license for the 40 MHz (8m) and 70 MHz (4m) band.

These are the frequency allocations with equipment.

8m: 40.680 - 40.700 MHz, all mode, max 50W out, ant modified 4elm 6m yagi (elem length adjusted)

4m: 70.000 - 70.500 MHz, all mode, max 100W out, ant 8elm LFA, fixed to Eu

Martin reports that he has already been heard by FG8OJ on Guadeloupe and K9MU in Wisconsin. 

Rcvr Band Mode Distance Time (UTC)
FG8OJ 8m FT8 865 km 18:16:14
K9MU 8m FT8 4243 km 16:58:44

Martin also reports a signal of -22dB in IM67 in the south of Portugal on 8m but it wasn't reported on the PSK Reporter website.

Martin also says that for 4m, he will be following the Region 1 band plan (Europe) and will be mostly operating on FT8.

Analysis... This is really excellent news as it opens up the possibility of a lot of interesting paths from this southerly location.


On 40 MHz, there will be plenty of openings on F2 up to the USA and Canada and will allow some contacts with the experimental stations there as well as crossband contacts and reception reports. Ironically it may be easier to get reports from the NE of the USA (3500-4000kms) than the SE which may be a bit too close.

There should also be plenty of openings to Europe, especially to Spain and Portugal. It should also open eventually to the UK and Ireland and the question is how far east into Europe will the signal travel.

In the Summer months, there should be plenty of multi-hop Sporadic-E openings from May to July and may act as an early warning for 50 MHz openings to follow.

What I find really interesting are the possible openings on 70 MHz.

Will amateurs in the USA and Canada be interested enough to listen on the band now that there is someone on from the Caribbean on 4m?

Will there be multi-hop Sporadic-E openings on 4m to Europe during the Summer? Almost certainly to Spain and Portugal but further north to the UK and Ireland? How far into Europe? Is it possible to get as far east as Cyprus? Further?


Looking at the southern hemisphere, there are a lot of interesting potential paths.

TEP openings on 40 MHz and 70 MHz to Argentina and the south of Brazil are a given. Will anyone there listen?

From Bonaire to the Falkand Islands (VP8) on 70 MHz?? Is it possible?

Bonaire to South Africa on 40 MHz should be possible on F2 but is it even possible on 70 MHz with multi-hop Sp-E? 11,000kms is a long way on 4m.

And what about the really long paths? From Bonaire to New Zealand (ZL) and Australia (VK) on 40 MHz???

We can be sure that some really interesting paths are going to pop up from this location.

Links for more info...
1) My 40 MHz page
2) My 70 MHz page

Addendum: Martin provides the following information of his permit.
1) 8M license is for 40.66 - 40.7MHz, max 50W, all modes. 
2) 4M license is for 70.0 - 70.5MHz, max 100W, all modes, Antenna restricted direction to Europe. Probably because Venezuela still has multiple analog TV channels in use in this range. 
3) Valid until Christmas 2023.

Friday, December 23, 2022

Two new pages for the blog...

 Over the last few years, I've written about a wide range of topics and even I have forget what I've written about! In the last week, I have added two new pages to the blog... one for the 432 MHz band and one for the Microwave bands.

Each page has a list of posts relevant to that area of interest and I think visitors will find it useful. It's certainly easier than trying to look for information in the blog archives.

***


If you are looking at the blog with a PC or Chromebook then you should see the list of pages near the top.

You can find the 432 MHz page HERE


You can find my Microwave page HERE

Thursday, December 22, 2022

70 MHz amateur band released in Switzerland from the Jan 1st, 2023


Some good news! Swiss radio amateurs will gain access to the 70 MHz / 4m band from the 1st of January 2023.

USKA is the IARU member society for radio amateurs in Switzerland and they released the following on the 21st of December.... "4m band released in Switzerland from Jan 1, 2023

After lengthy negotiations with OFCOM, the USKA was able to release the 4m band. The approval is valid from 1 Jan 2023. The following operating conditions apply:

Only radio amateurs with HB9 licenses are allowed to use the band.
Frequency range: 70.0000MHz to 70.0375 and 70.1125 to 70.5000MHz.

Any transmission is prohibited in the range from 70.0375 to 70.1125 MHz.

The maximum power is 25 watts ERP
All common types of modulation are allowed. Use according to the IARU band plan is suggested.
The band is to be used for direct connections. Unattended stations such as relays and Echolink gateways are not allowed.
Remote-controlled stations require a report to OFCOM.
The USKA wishes all 4m enthusiasts every success in exploring the new 4m band.

Bernard Wehrli, HB9ALH - OFCOM liaison officer
"

What to expect???....... See the map below...


Even with an ERP of 25-watts, HB9 stations should have no problem working out to 500kms with weak signal modes.

In the Summer months, Sporadic-E will be the main propagation mode. Stations in the 1000 to 2200 km range should be easy to contact with a peak around the 1500-2000km mark.

Multi-hop Sporadic-E is always possible so there will be more exotic paths.

Source: https://www.uska.ch/4m-band-in-der-schweiz-ab-1-jan-2023-freigegeben/

Thanks to Andrea, HB9DUR for the info source.

Wednesday, December 21, 2022

OZ7IGY 40 MHz beacon in Denmark is transmitting again - Dec 2022


In a previous post on the 30th of November 2022, I wrote about how the OZ7IGY team in Denmark had  announced that their 8m beacon on 40.071 MHz has been turned off due to increased electricity costs.

The good news is that a few days later on the 5th of December 2022, they announced the following... "The 40 MHz beacon is back on the air. The 10 GHz beacon is now off the air.... OZ7IS"

This is good news as it would be nice to have the 8m beacon operational for the peak of the sunspot cycle.

Annual sponsorship of one individual beacon for one year costs 1400 Danish Krone which is about €190.

OZ7IGY website... http://www.oz7igy.dk/

2022 Reports... Looking at the DX Cluster, there are plenty of reports for the OZ7IGY beacon on 40.071 MHz but they are all from Europe. I'm open to correction on this but I have seen no reports from South Africa, South America or North America.

There are plenty of reports of Trans-Atlantic paths on 40 MHz from the USA to Ireland and UK but what about Denmark?


It's further east and the path would be more northerly. Can it be heard outside of Europe?

A plan of action... The OZ7IGY beacon is on both 28.271 MHz and 40.071 MHz. A good place is start is on 10m. Put your receiver on 28.2702 MHz USB and listen for the CW beacon. Try to use the PI4 software and get experience with it to decode the PI4 signals.

If the 10m beacon is a reasonable signal strength then repeat the experiment on 40.0702 MHz USB.

The key point here is that if you are interested in the 40 MHz band then don't spend all your time on 40.680 MHz. Try the other beacon frequencies and report what you hear.

Link...
a) My 40 MHz page

Tuesday, December 20, 2022

Guide prices for the upcoming ICOM IC-905 Microwave Transceiver


On Sunday the 18th of December 2022, ICOM Japan held their own exhibition at their Narayama Research Institute to display some of their new projects. This included the upcoming IC-905 transceiver which will cover 144 MHz, 432 MHz, 1296 MHz, 2.4 GHz & 5.6 GHz. They also have an optional 2.4 GHz to 10 GHz transverter.

I won't go into the full details of the radio here but you can read about it in my previous post HERE

The big question is what is the price going to be and when will it be released? In my earlier post, I guessed that it might be in the $2000 to $2800 price range.

HAMLIFE . JP reports on Twitter from the exhibition that the guide price for the IC-905 will be 400,000 Yen. This is around $2930 or €2760.

The optional 10 GHz transverter will be 150,000 Yen which is about $1100 or €1040.

The release date is expected to be the Spring of 2023 which is a bit earlier than I was expecting.


Now the unknowns are... 
Will it be too expensive???
What will the demand be like???
Will the demand be different in the various markets... Japan / North America / Europe / Australia ???

Interesting times ahead.

Links...
3) More IC-905 info on my Microwave Page

Mid-Winter Sporadic-E opening on 28 MHz - Mon 19th Dec 2022


Normally the main Sporadic-E season normally lasts from May to August every year but there is also a smaller secondary peak during the Winter months. While I was listening for WSPR signals on 28 MHz yesterday, I noticed that there was a Sporadic-E opening on the band.

While this isn't that unusual, what caught my attention was the fact that the skip distance was short for 10m and I was hearing stations in England. The map above shows some of the European stations that I heard on WSPR including a batch in England.

Most of these English stations were in the region of 500-700kms which is reasonably short and unusual. It's much easier for me to hear say German stations during a Sporadic-E opening as they are around the 1200-1500km mark.

What alerted me to the short skip was the sound of the QRSS signals from England coming through on the WSPR frequency of 28.1246 MHz.


QRSS is a very slow form of morse code where a single callsign is sent over a period of a few minutes and the call can be decoded by looking at the audio spectrum on a screen. Signals that are up to 20dB below the noise level can be seen and in a way, this was the original 'buried in the noise' signal mode before the likes of FT8 and WSPR arrived on the scene.

In the example above, the 10m QRSS signals are about 500Hz below the WSPR signals and in the same audio passband.

It's likely there will be more Sporadic-E openings on 28 MHz and 50 MHz over the Christmas period, have a listen.

Saturday, December 17, 2022

Trans-Atlantic opening on the 50 MHz band - Fri 16th Dec 2022


There was an interesting trans-Atlantic opening on the 50 MHz band between Europe and North America on Friday the 17th of December 2022 and it looks as if it was either F2 layer or multi-hop Sporadic-E propagation.

The map above shows the 50 MHz paths open via FT8 for AB1OC in New Hampshire. There is evidence of plenty of Sporadic-E activity to the eastern half of the United States but several stations in the UK and Ireland can seen.

Txmtr Rcvr Band Mode Distance Time (UTC)
G0CHE AB1OC 6m FT8 5265 km 15:14:44
G4IFX AB1OC 6m FT8 5244 km 15:16:44
AB1OC M0DEP 6m FT8 5194 km 15:13:29
G0GGG AB1OC 6m FT8 5149 km 15:15:14
AB1OC G0HVQ 6m FT8 5117 km 14:38:26
G4RRA AB1OC 6m FT8 5055 km 15:10:44
AB1OC G8IXN 6m FT8 4979 km 14:42:29
EI7GUB AB1OC 6m FT8 4819 km 14:24:14
AB1OC EI3KD 6m FT8 4728 km 14:32:29
EI2IP AB1OC 6m FT8 4688 km 15:09:44

There are plenty of openings on the 50 MHz band at the moment but most of them are from areas closer to the equator. In the last week or so, there have been some very long paths across the Pacific from Australia and New Zealand to the USA. What makes the North Atlantic opening interesting is that it was East-West and it was from a northerly latitude.

It looks as if the opening itself was reasonably modest and it was mainly confined to what might be described as 'large stations' i.e. the numbers were in the tens rather than the hundreds.

WW1L in Maine and W3UR in Maryland have similar list of FT8 across the Atlantic...

Txmtr Rcvr Band Mode Distance Time (UTC)
G0CHE WW1L 6m FT8 4965 km 15:15:14
G4IFX WW1L 6m FT8 4945 km 14:49:44
WW1L M0DEP 6m FT8 4894 km 14:44:28
G0GGG WW1L 6m FT8 4850 km 15:15:14
G0HVQ WW1L 6m FT8 4817 km 14:54:44
WW1L G0HVQ 6m FT8 4817 km 14:47:56
WW1L G7RHF 6m FT8 4779 km 14:53:27
WW1L G4RRA 6m FT8 4756 km 15:33:59
WW1L G8IXN 6m FT8 4681 km 14:40:59
EI7GUB WW1L 6m FT8 4518 km 14:13:14
WW1L EI3KD 6m FT8 4428 km 15:02:29

Txmtr Rcvr Band Mode Distance Time (UTC)
G0CHE W3UR 6m FT8 5858 km 15:16:14
W3UR G4IFX 6m FT8 5838 km 15:31:58
W3UR M0DEP 6m FT8 5787 km 14:59:28
W3UR G0GGG 6m FT8 5743 km 14:59:30
W3UR G0HVQ 6m FT8 5711 km 14:59:56
W3UR G7RHF 6m FT8 5673 km 14:59:29
W3UR G4RRA 6m FT8 5648 km 15:31:59
W3UR G8IXN 6m FT8 5571 km 15:31:59
W3UR EI3KD 6m FT8 5321 km 15:33:29


Looking from the eastern side of the Atlantic, the FT8 paths for EI3KD on the south coast of Ireland are shown above. I've included the full path lists for EI3KD and G1IFX at the end of this post.

Analysis... This post certainly isn't an exhaustive list of who worked what but it gives an overview of what the 6m trans-Atlantic opening was like. The big question is if the opening was via the F2 layer or was it multi-hop Sporadic-E like during the Summer months?

In the last three days, there have been 29 M-Class flare from the sun and the solar flux on the 16th was up to 166. It would suggest that F2 propagation might be one explanation. There were some Sporadic-E openings on the day in Europe and North America so the possibility of trans-Atlantic multi-hop Sporadic-E can't be ruled.

Paul Logan, MI3LDO reports that conditions in the low VHF band (~40 MHz) suggests that it was more likely to be Sporadic-E rather than F2 layer.

It's worth remembering that the peak of this sunspot cycle is unlike all of those that came before. Now most radio amateurs are using weak signal modes like FT8 and are listening for signals buried in the noise. In the previous cycles, CW and SSB were the dominant modes.

I didn't see any reports of CW or SSB contacts for the trans-Atlantic opening on the 16th and I'm quite sure that without FT8, it would have been a much smaller affair with just a small few stations making contacts.

The take home message is that if it was F2 propagation then it's likely to happen again. If it was multi-hop Sp-E Sporadic-E then it may not occur again for a while. Keep those beams pointing across the Atlantic and wait for the next 6m opening.

Cont...

FT8 paths for EI3KD in Ireland...

Thursday, December 15, 2022

Listening for the CAS-5A Chinese satellite at 435 MHz - 15th Dec 2022

CAS-5A is a Chinese amateur radio satellite which was launched from the Yellow Sea off China on the 9th of December 2022. It's an unusual satellite in that it has transponders with an downlink in the 70cms band and uplinks on the 2m VHF band and the 15m HF band.

Today on the 15th of December 2022, I did a quick test to see if I could hear it. The pass was from 15:18 to 15:30 UTC with the satellite reaching a maximum elevation of 44 degrees above the horizon. 

The satellite has a CW beacon on 435.570 MHz so I left my radio listening on that frequency on USB. My antenna was a very modest home made colinear vertical antenna in the attic of my house.

My primary objective was to catch the doppler shift of the beacon and my secondary objective was to listen for any activity in the transponder passband.

The image on the left shows the audio spectrum of the received audio from my radio. The trace showing the drifting CW beacon can be clearly seen. In the space of just 15 or so seconds, the CW signal had moved downwards about 1KHz in frequency due to doppler shift. 

As you might imagine, this make manual tuning of a CW or SSB  signal on the 70cms band quite a challenge and confirms the need for some sort of CAT software to control the frequency of the radio to compensate for the doppler.

The signal of the CW beacon was also quite weak and was just above the noise. I'm sure that a pass overhead would probably be stronger but the beacon is still only 100mW to a whip antenna. The test confirmed to me that a small crossed Yagi antenna would probably be much better.

As for activity on the satellite, I did tune upwards after the beacon test and I could hear the weak warble of a FM signal on SSB but it was too weak to hear on FM mode.

The CAS-5A satellite has been given the AMSAT name of FO-118. A users manual for the satellite can be viewed HERE

Monday, December 12, 2022

5300km TEP opening on 144 MHz from South America to the Caribbean - 11th Dec 2022


It's interesting to see that there are once again some great openings between South America and the Caribbean on 144 MHz vie Trans-Equatorial Propagation (TEP). Distances achieved are in the region of 5300kms.

The map above shows a path from LW2DAF to PJ4GR although there were other paths as well from Puerto Rico to the south of Brazil.

This video clip shows a SSB contact on 144.300 MHz between Diego, LW2DAF in Argentina and PJ2VR on Curacao. Note the warble!

These are some of the spots from the DX-Cluster...
Spotter Freq. DX Time Info Country
YV4AKK 146520.0 LU1JAS 01:14 12 Dec 5/9 20 Argentina
YV4AKK 146520.0 LU9ELY 01:12 12 Dec 5/7 Argentina
LU5FF 144300.0 PJ2VR 00:42 12 Dec FF99rf<>FK52mf tnx QSO Curacao
PY3SOL 144300.0 YY7CAR 00:21 12 Dec 5/1 VERY HAPPY DAY!!! Venezuela
PY3SOL 144300.0 NP4JJ 00:06 12 Dec 5/5 SSB Puerto Rico 
PY3SOL 144300.0 WP4KJJ 23:53 11 Dec 5/9++ Puerto Rico
NP4BM-@ 144300.0 PY3SOL 23:40 11 Dec 5/9 + tep qso Brazil
PY3SOL 144300.0 NP4BM 23:40 11 Dec 5/9+ Puerto Rico

It would be very interesting to know...

1) Are any of the stations in South America or the Caribbean trying TEP contacts on 432 MHz???

2) Is there are 144 MHz TEP activity from Africa to Europe???

Links...
1) More information about previous TEP contacts can be found on my 144 MHz page.

Sunday, December 11, 2022

Article in the Space Chronicle journal about EIRSAT-1


'EIRSAT-1' stands for 'Educational Irish Research Satellite' and it will be Ireland's first satellite. It is a 2U CubeSat being developed as part of the European Space Agency's Fly Your Satellite programme.

The satellite which cost €1.5 million to develop will carry three science experiments and the downlink frequency for the data will be in the 145 MHz amateur radio band. It is expected to launch in 2023.

The British Interplanetary Society have an article about the new Irish satellite in their quarterly Space Chronicle journal. The January 2023 edition is available to members of the British Interplanetary Society... info HERE

EIRSAT website... https://www.eirsat1.ie/

Friday, December 9, 2022

Square Kilometre Array Radio Telescope in Australia to cover 50 to 350 MHz


The Square Kilometre Array (SKA) is an international radio astronomy project with the object of scanning the cosmos from 50 Mhz to 15.4 GHz.

This project was originally conceived in 1991. The first 10 years were about developing the concepts and ideas. The second 10 was spent doing the technology development. And then the last decade was about detailed design, securing the sites, getting governments to agree to set up a treaty organisation (SKAO) and provide the funds to start.

There are two key sites. The SKA-mid array in South Africa covers 350 MHz to 15.4 GHz and it uses dish antennas. In this post, I'll focus on the SKA-low array in Western Australia which covers 50 MHz to 350 MHz.


The SKA-low array will be located at a remote site near Murchison in Western Australia. Bulldozers are expected to start working on the site in early 2023, with the completion date estimated as 2028. 

The array is described as follows... "a phased array of simple dipole antennas to cover the frequency range from 50 to 350 MHz. These will be grouped in 40 m diameter stations each containing 256 vertically oriented dual-polarisation dipole elements.". 

"Stations will be arranged with 75% located within a 2 km diameter core and the remaining stations situated on three spiral arms, extending out to a radius of 50 km."


While the array description is of 'simple dipole antennas', the 'Christmas Tree' antenna is actually a log-periodic antenna with two polarisation feeds. There seems to be a metallic grid underneath to maximise the gain upwards.


While the gain of each individual antenna is low... possibly in the region of 6dBd... it's the sheer number of antennas fed in phase with each other that gives the high gain and resolution.

The array will produce up to ~5 Tb/s (or ~ 700 GB/s) of measurement data, which is equivalent to downloading ~200 High-Definition movies in one second. This data will be transported via a dedicated fibre from the Murchison Radio-astronomy Observatory to the SKA-Low science processing centre located in Perth. 

As might be expected, all radio transmitters are banned from the area to maintain a low noise environment. The Murchison site is about 600kms to the north of the city of Perth and is very remote.


Videos... Sirio are probably better known to the radio community as the manufacturer of various types of CB antenna as well as some for the VHF amateur bands. Their antenna plant in Volta Mantovana (Italy) will produce 78,000 'Christmas tree' antennas which will go to Western Australia to form the low-frequency part of the SKA telescope.

1) The video is in Italian but YouTube does a good job of translating it...

2) This second video titled 'Making the SKA telescopes a reality: the next chapter' gives an overview of the SKA project.

It is expected that the Square Kilometre Array project will contribute to many areas of radio astronomy.

These include...
Signals emitted in the first few hundred million years after the Big Bang.
Trace the full history of hydrogen, the most abundant element in the Universe.
Detect hydrogen's presence even before great clouds of it collapsed to form the first stars.
Fast radio bursts which output the equivalent of an entire year's worth of energy from our Sun in just a fraction of a second.

Links...
1) For more information on the SKA project, go to https://www.skao.int/

Wednesday, December 7, 2022

Big opening on the 40 MHz band - 7th Dec 2022


Wednesday 7th December 2022: With the Solar Flux up at 148, the F2 MUF is now extending well above 30 MHz and into the low VHF spectrum. The map above shows some of the FT8 activity on the experimental 40 MHz band on the 7th of December.

The stations in South Africa (ZS), Slovenia (S5), Croatia (9A) and Ireland (EI) are radio amateurs who have permission to use this band. The stations in the USA, Canada and the UK are using experimental licences for transmitting.

I have a full list of the stations decoded at the end of this post. I'm not sure about a few of the transmitting callsigns as there may have been some mistakes and the wrong band was reported.

Martin, PJ4MM on the island of Bonaire in the Caribbean sends the following report...

 Just copied multiple stations from EU on 8M:

G9PUV JO00 ft8 +20  S9 on meter)
EI2IP IO52 ft8 +22  S9 on meter
EI4GNB IO63 ft8 +12
S50B JN65 ft8 -6
S59F JN65 ft8 -1
9A5CW JN65 ft8 -8
The G and EI stations were loud enough for SSB. Opening started ~1530Z and lasted until 1629Z

Last Monday (5th Dec) copied:   144230  6  0.1  798 ~  CQ WM2XEJ EM83  (ft8). Opening lasted ~30min
And on Sunday 20221204 (wspr):
2022 -23  0.11  40.6814841  WM2XCC DM13 33
2040 -13 -0.15  40.6814851  WM2XCC DM13 47
2102 -27  0.15  40.6814844  WM2XCC DM13 33
RX: IC7300, Antenna modified 6m 4el with increased element length

Link: My 40 MHz page

Full log of activity is shown below...

Sunday, December 4, 2022

Communication experiments in Japan at 5600 MHz and 10 GHz using the ICOM IC-905


On the 17th of November 2022, ICOM staff in Japan conducted some experiments over a 25km obstructed path on the 5.6 GHz and 10 GHz microwave bands with the company's new IC-905 transceiver.

The photo above shows the view from the roof top of the six story building at ICOM's headquarters in Osaka. The two parabolic dishes for 5.6 GHz and 10 GHz are beaming towards the Ikoma mountains. The RF module of the IC-905 and the 2.4 GHz to 10 GHz transverter are also shown. The station at ICOM HQ was JK3AZL.

The second portable station JL3ZAB with a similar setup was operating from a hill near Kizugawa City which was about 25kms away on the other side of the Ikoma mountains. The map below below shows the path in Blue. The important point here is that both stations were blocked from each other by the mountains but both were line of sight to Mt Ikoma.

Both stations started early in the morning, setting up their radio equipment and antenna systems. By 9am, both stations were able to easily catch each other's signals by pointing their parabolic antennas at the summit of Mt Ikoma using a map and compass and were able to communicate by voice on both the 5.6 GHz and 10 GHz bands.

It is believed that the propagation mode was knife-edge diffraction from the mountain peaks.

The power of the IC-905 is 2-watts at 5.6 GHz while the output power of the 10 GHz transverter is 1-watt.

The test was repeated later with JL3ZAB now operating from the ICOM Narayama Laboratory. From this lower location, the summit of Mt. Ikoma was now longer visible. They were barely able to communicate on 5.6 GHz with CW while communication at 10 GHz was not successful.

The path from ICOM HQ to their Narayama Lab is shown above in Red. The path profile is shown below albeit with an exaggerated vertical scale.


The ICOM team concluded... "It is known that in the SHF band or even higher frequencies, radio propagation gradually becomes more linear, similar to light. The Icom team thought it would be interesting to see whether communication will be impossible under non-line-of-sight conditions as in this case, or whether communication by mountain diffraction (Knife-edge effect), known as anomalous propagation, would be possible.

The experiment revealed that mountain diffraction phenomena occur even on mountains with relatively gentle peaks such as the Ikoma Mountains. Conversely, if the peaks are not visible, communication is difficult."


Analysis...
Once the ICOM IC-905 goes on sale, people that purchase it may well expect only line of sight contacts as that will be the mantra of most websites and commentators. With high gain antennas and weak signal modes, there will be many unusual paths like the example above.

In an urban environment, there may well be many reflections off objects like high buildings, water towers, masts, etc.

If you consider that tropospheric ducting often occurs more often at microwave frequencies then there are bound to be surprises for those who are interested in experimenting on these amateur bands above 1 GHz.

News source... https://www.fbnews.jp/202212/w_news03/

Link...

a) More info about the IC-905 on my Microwave page

Thursday, December 1, 2022

40 MHz & 60 MHz Facebook Group now has over 500 members


Just a quick update to say that the 40 MHz & 60 MHz Group on Facebook now has in excess of 500 members. As the chart shows above, it has more than doubled in the last year.

The level of interest in two obscure experimental amateur radio bands in the low VHF spectrum has been a bit of a surprise to me. I initially thought the group would struggle to get to 100.

If you have a genuine interest in keeping up with the experiments and activity on the band then you can find the group here... https://www.facebook.com/groups/2897330140356898

Wednesday, November 30, 2022

40 MHz beacon in Denmark off air due to electricity costs


The OZ7IGY team in Denmark have announced that their 8m beacon on 40.071 MHz has been turned off due to increased electricity costs.

They write... "The 40 MHz, 2,4 GHz, 3,4 GHz, 5,7 GHz and 24 GHz beacons are all off air due to the increased price of electricity. It is currently impossible to say when they will be back on the air. 

OZ7IGY has an annual electricity bill of more than 20 000 DKK, equivalent to about 2800 EUR given normal electricity prices. Unfortunately Denmark is among the most expensive countries when it comes to the cost of electricity. But we are also looking for equipment support in our continuous strive to make OZ7IGY the best beacon in the world.

As of October 2022 the annual electricity cost will exceed 7000 EUR.  – 2022-10-17"

The beacons at 28 MHz, 50 MHz, 70 MHz, 144 MHz, 432 MHz, 1296 MHz & 10 GHz remain operational.

Annual sponsorship of one individual beacon for one year costs 1400 Danish Krone which is about €190.

OZ7IGY website... http://www.oz7igy.dk/

Sunday, November 27, 2022

Upgrade of WSJT-X software and the 40 MHz band


Just a post of some notes for my own benefit although others might find it useful as well.

Even when I wasn't updating the blog for the last six months, I was still using the radio in that I left it monitoring the WSPR frequency on 28.1264 MHz every day. The software I was using on the PC was WSJT-X with quite an old rev V2.0.1 which I think is from 2019?

I never really bothered updating the version I had as it decoded WSPR and FT8 signals fine. I know my old version didn't decode the 'new' FT4 mode but I wasn't too bothered about that.

I tried listening for some of the Irish 40 MHz beacons this morning. I managed to get two two successful decodes from EI1CAH on 40.16 MHz using the PI4 mode. I think this was via aircraft scatter.

The other beacon EI1KNH on 40.013 MHz uses several modes including FT8 so I had to be careful as I didn't want to 'hear' something on 40 MHz and have my PC upload it to PSKReporter as a 28 MHz signal.

The problem with my old version of WSJT-X and FT8 is that it doesn't support any 40 MHz operation. So I downloaded the latest version of WSJT-X from the Princeton University website... V2.5.4

It essentially looked the same when I ran it. From the default settings, it doesn't show 8m (40 MHz) as a band option.


Under 'File', I had to go to 'Settings...' and then click on 'Frequencies' as can be seen above.

There are loads of options here... I picked the one that was All mode on 24 GHz as I was pretty sure I wouldn't need it 😉

Then it's just a case of double clicking on it and changing the frequency. I chose 40.680 MHz... and then clicked ok.

When I went back to the main programme then, I had 40.680 MHz on 8m as a band option.


In the end, I didn't manage to any FT8 decodes from the beacon but I probably need to improve my antenna system.

At listen I can report any signals that I hear now.

Addendum... I finally managed to decode one FT8 transmission from EI1KNH which I think was from aircraft scatter again.

Saturday, November 26, 2022

Antenna upgrade for the GB3NGI 432 MHz beacon

The GB3NGI beacon transmits on 432.482 MHz on the 70cms band and it is located on the summit of Slieve Annora in County Antrim in the north-east of Ireland. The site is 500-metres above sea level and it's locator square is IO65VB.


It has as far as I know been operational since 2014 and beams to the south-east towards London.

The beacon keeper Gordon, GI6ATZ reports that the antenna system has now been updated...

GB3NGI 70cms Beacon: - The single 70cms yagi was replaced today (22nd Nov 2022) by a pair of Antenna- Amplifiers 9 ele yagis beaming NE and SE

This should improve the coverage quite significantly up to the NE and whilst in theory it should be at least a 3dB reduction in power to the SE my initial test here show a significant increase in signal strength - but then I am relatively close to the beacon!

The old antenna had suffered quite a bit of damage and I suspect the driven element assembly was full of water. 

Would appreciate signal reports with the new antenna system particularly from the NE but also from the SE to see if people notice any improvement/reduction in signal strength. 

The map above shows the location of the beacon and the new beam headings of 45 degrees (north-east) and 135 degrees (south-east). 

In the past, areas like Glasgow and Edinburgh were on the side of the old beam so the new system should result in a much stronger system.

The beacon has an RF output power of 20 watts and transmits JT65b on the even minutes and CW on the odd minutes in the following sequence: -

00:01 – 00:51 GB3NGI IO65VB in JT65b mode
00:52 – 01:00 GB3NGI IO65VB in CW
01:01 – 01:29 Plain Carrier
01:30 – 01:40 GB3NGI IO65VB in CW
01:41 – 02:00 Plain Carrier
The sequence then repeats

To decode the JT65b, tune the carrier to obtain a tone of 1500Hz with the receiver set to USB, and the dial frequency reading 432.4805. The JT65b will then be tuned in correctly.


The antennas used for the 432 MHz beacon are a pair of 9-element Antennas-Amplifiers Yagis designed and built by Goran YU1CF :- https://antennas-amplifiers.com/product/70cm-antenna/70cm-rear-mount-wideband-strong-yagi/

Additional information...

1) GB3NGI website

Wednesday, November 23, 2022

HF & VHF Ocean Radars - 26 MHz to 43 MHz

HF & VHF Ocean Radars - 26 MHz to 43 MHz

I received an email recently from Rob, PE9PE looking for the email address of Des, EI5CD to pass on some information about some unusual signals at the bottom of the 26 MHz band. I didn't have the email info but I thought the information would make an interesting post and I'm sure Des will see it as well.


The concept of Ocean Radars is quite simple... a radio pulse is sent out by a transmitter at the shoreline, some part of the signal is scattered by waves on the ocean and this is picked by a receiver back at the coast.

It's described as follows... "How it works: We measure ocean currents by emitting radio waves from shore-based transmitting antennas that travel along the ocean's surface. The radio waves are scattered by the rough surface of the ocean (ocean waves) and part of the scattered energy returns like an echo to a receiving antenna.  The received echoes contain information about the range, direction, and speed of the current in relation to the antenna location. Combining this information from two or more antennas allows us to construct surface maps of current speed and direction."

The ITU frequencies for these systems are as follows:

a) On the lower part of the HF bands, they are at 4.4 MHz, 5.2 MHz and 9.3 MHz.

b) On the higher HF bands, they are at 13.5 MHz, 16.1 MHz, 24.5 MHz and 26.3 MHz.

c) In the low VHF spectrum, they are at 39.2 MHz, 41.4 MHz, 42.2 MHz and 43.5 MHz.

My main interest here are the systems operating at 26 MHz and above and how they might be used as a propagation indicator. There may be more frequencies but these are the ones I am aware of for now.

Systems... There seems to be two main companies in this space.

1) CODAR OCEAN SENSORS from the USA have their SeaSonde system and their website is https://codar.com/


As their information document above shows, the antenna for this system is just a vertical whip. 

When someone mentions a 'radar system', I think most of us imagine some sort of huge antenna array with many kilowatts of RF power. From the information I could find, it seems that 50-watts is typical power level.

Some use a small array of vertical whips side by side which probably help focus the signal on a certain area but it's nothing too elaborate.

There seems to be examples of these located at quayside walls next to where the public are walking so the power density is low.

An example of what the CODAR signal sounds like can be found here (just click on the audio sample on the right)... https://www.sigidwiki.com/wiki/CODAR

2) The other company is HELZEL from Germany and their website is https://helzel.com/

This is an example of their WERA VHF system...

High resolution VHF WERA - ITU bands 39.2, 41.4, 42.2 and 43.5MHz
Characteristics:
Typical range resolution of 300m
Best for highest resolution current measurements up to 25km
Wave measurements for Hs >0.2m for ranges of up to 10km
These systems use very small antennas and short arrays
Best suited for mobile applications

This is a map of some of their systems operating in Europe as of Q4 2022...


They don't mention what frequency... HF or VHF... is used by each one of these locations but I'm sure many of you will be living near one and wondering what it is.

After Rob told me about these signals, I found one around 26.300 MHz. I found it best to listen on AM and have the filters as wide as possible. In my case, that was 12 kHz.

It sounds like a rapid ticking or clicking noise. If you could imagine say a clock ticking once per second then this radar system sounded something like 3 ticks per second.

I don't have a sample of it to include in this blog post but it's easy to recognise.

Video... This video about the SeaSonde system gives an overview of its purpose...



Propagation indicator... Can we make use of them? While it will be very difficult to identify the location of any individual ocean radar system, they can still be used as a sign that a band is open.

There are many instances of when 21 MHz is open and 28 MHz is dead or 28 MHz is open and 50 MHz is dead. At least these ocean radars give some warning of improving conditions on a frequency in between.

Low Band VHF... There seems to be a general assumption that low band VHF (30-50 MHz) is dead and most of the users have migrated to the higher UHF bands. This is one instance where low band VHF and it's particular wavelength has a useful application and niche.

Q. Do you have an ocean radar system operating near you? Let me know your location and it's frequency and I'll add it to the post for reference.

Wednesday, November 16, 2022

Video presentation on the QRP Labs QDX 5-watt Digital Transceiver


Four Days in May (FDIM) is an annual QRP convention that is held in Dayton, Ohio. A series of talks are usually given and for the 2022 event, there was an interesting presentation given by Hams Summers (G0UPL) about his new QDX transceiver kit.

This is a 5-watt radio for the 80m, 40m, 30m and 20m bands and is designed for digital modes like FT8. The basic kit currently retails for just $69 but there may be additional costs like import duties. It is still a very cost effective way of getting on the bands especially when you consider how many main brand radios costing $1000++ must be sitting on one frequency doing FT8 day after day.

Hans writes on his website... "QDX is suitable only for single tone FSK modes, which covers the majority of digital modes in use today. This includes everything in WSJT-X, JS8Call, some fldigi modes e.g. RTTY, Olivia and more. QDX is not suitable for on/off keyed modes such as CW because it does not have click-reducing RF envelope shaping; furthermore it is not suitable for phase shift keyed modes such as PSK31 or modes involving multiple concurrent tones such as WinLink,"


The QDX is supplied with the surface mount parts already on the PCB but some level of experience is still required to build and assemble this kit. I don't think it's for absolute beginners.


The power output versus the supply voltage is shown above. As the frequency is relatively low... 3.5 MHz to 14 MHz... the performance of the output stage is pretty good.

Hans did mention that there are plans for a similar radio covering 20m to 10m ...14 MHz to 28 MHz... and the challenge then will be to have a reasonable output at the higher frequencies.


Demand for this kit has been huge so check on the QRP Labs website for availability. There is also a lot more information about the radio on that site.

The presentation itself covers the basics of digital modes before exploring what is going on in the QDX radio.


The video of the presentation which was only put up on YouTube on the 14th of November 2022 is about an hour long but the audio level is very low. I had to use headphones to listen to it.