Very long distance contacts in the region of 5000-6000 kms on 144 MHz from the Caribbean to the south of Brazil, Uruguay and the area near Buenos Aires in Argentina are reasonably common via TEP (Trans-Equatorial Propagation).
The geometry is just right for these contacts ...a) Population centres at each end of the path with active amateur radio stations ...and b) At right angles to the Geomagnetic Equator.
This map from the 2nd of February 2022 shows a typical opening...
All the paths tend to be parallel to each other as they cross the Geomagnetic Equator at 90 degrees. However even in the example above, you can see a few paths that are not exactly parallel.
LU7MC... Carlos, LU7MC is in the west of Argentina and active on 144 MHz for many years. His location is shown on the map at the top of the post in the far west of Argentina. For Carlos, the other end of his usual TEP path falls in areas further west in the Caribbean around Jamaica and Cuba, areas where there is very little 144 MHz activity.
Carlos writes..."I always wondered the same thing, why no TEP? Many years ago my interest in VHF DX awoke and I began to investigate. I believe that one of the main obstacles is the small number of operators who, are unaware of TEP and miss out on the opportunity to experiment with the different types of propagation at 144 MHz and higher.
After a long time of trying (13 years) it finally happened!! A TEP contact from the west of South America on 144 MHz : LU7MC - HI3I Q65B 5827Km, Very atypical conditions where the strict Trans Equatorial propagation theory seems not to apply. It was always thought that it would occur with stations further west in the Caribbean."
As Carlos writes, it does seem to have been an unusual TEP opening where the path was not quite a right angles to the Geomagnetic Equator.
It also shows that location is everything for TEP... someone near Buenos Aires can almost make daily 144 MHz contacts on TEP with the Caribbean at certain times of year and someone in the west of Argentina has to wait 13 years!
Carlos sent on a few images. This one shows the predicted map of the critical frequency of the ionosphere around the time of the TEP opening. Notice the less intense zone over the Geomagnetic Equator in South America and the more intense region either side which sets up the perfect conditions for a TEP opening.
This screenshot from Carlos shows that the contact was made on 144.180 MHz using the Q65B weak signal mode. Signals are in the region of -12 to -14dB which is just about detectable to the human ear. A CW contact would be very difficult at this signal level.
Note that the time is in UTC. Evening time TEP usually peaks around 8pm local time.
This final image shows the solar conditions on the left with the Solar Flux at 138 and the K index at 1.7. The right hand side of the image shows the confirmation of the contact via LOTW (Logbook of the World).
Chile (CE) ??? ...Now that there has been a successful TEP contact on 144 MHz from the west of Argentina, what about Chile? Is TEP possible from Santiago? Are there any stations in the west of the Caribbean interested in 144 MHz?
220 MHz and 432 MHz??? ...I would be interested to hear of any TEP openings at 220 MHz or 432 MHz. Will the distortion make digital weak signals modes unusable at the higher frequencies?
Thanks for Carlos, LU7MC for the above information and congratulations on your FB TEP QSO.
Link... 1) For more TEP contacts, check out my 144 MHz page HERE
There is an active group of radio amateurs in Australia and New Zealand using the WSPR mode on the 144 MHz band to investigate propagation paths. On Christmas Day, VK5PJ in Adelaide managed to get just one WSPR decode from ZL2GT on the North Island in New Zealand.
Local (y-m-d)TXtxGridRXrxGridMHzWSNRdriftkm 2022-12-25 09:12ZL2GTRF80VK5PJPF95mk144.49049810-1803385
Leigh VK2KRR reports... "144 MHz antics for some operators yesterday. Peter Sumner VK5PJ and ZL2GT topping the maximum distance at 3385 km via Sporadic E.
There was a number of other E paths and tropo as well. Another path of note is Nigel VK6CPU at Perth on a path with Phil VK5AKK tropo path at 2140 km. Its rare to get paths into and out of Perth on tropo, but it does happen on rare occasions.
A few days back i missed reporting on a tropo path from Alan Johnson VK3DXE to VK6CPU/P of 2442 km. Alan was the only station in VK3 who made it on this path on 23.12.22."
Analysis... The extreme distance of this opening i.e. 3385 kms, cannot be explained by a single Sporadic-E hop which tends to max out around 2300 kms.
This is the tropo forecast for the 25th of December 2022 from F5LEN...
It does suggest that there were some tropo conditions in the Tasman Sea but it's not conclusive. It's probable that the western path of the path was certainly due to Sporadic-E but as for the eastern half, it may have been due to a tropo extension over the Tasman Sea or it may have been a second Sporadic-E hop i.e. possibly chordal hop Sporadic-E.
People may have different opinions on which it is but it's almost impossible to tell.
Links... 1) Examples of more long distance contacts on 2m can be found on my 144 MHz page HERE
Very long distance propagation paths on the 144 MHz band are always of interest and those that exceed 3000kms are especially so. In Australia and New Zealand, there are quite a number of radio amateurs using the WSPR beacon mode to cary out propagation tests.
Leigh, VK2KRR reports on a special 3051 km opening on 144 MHz on the 24th of December 2022. It should be noted that countries in the southern hemisphere are now in the middle of their Summer Sporadic-E season.
Leigh writes..."This afternoon 24.12.22 at 0524z I noticed a report on WSPRview of VK2EFM to VK6CPU/p on 2m at 3051 km. Initially I thought it must be a mistakenly reported spot sent to wrong band, but upon further investigation and discussion with those involved, it appears this spot was real, which is quite unbelievable really considering the circumstances at the time.
The crazy part about it was that the propagation was well in decline from a quite good high MUF period which had lasted a number of hours with MUF reported up to 107.7 MHz and path covering a good deal of southern Australia.
Coincidentally at the same time there is also tropo propagation across the Great Australian Bight from VK5AKK to VK6CPU/p and VK6NI.
To make it somewhat more questionable, Allan Savins VK2EFM transmitted on both 6m and 2m WSPR at the same time at 0524z as was demonstrated by the local reports.
The propagation question would be, how did the signal get across? A double hop E, a Chordal E? or maybe a single E hop then into tropo ducting across the Bight?
Notice the path exactly lines up with the VK5AKK tropo path, which is interesting.
Also of note is that there was no reception of any 6m WSPR signal from VK2EFM in VK5 or VK6 at 0524z, the max distance was 440 km to myself which was probably some sort of backscatter.
The last 6m reception of VK2EFM in VK5 was 12 mins prior to the 2m path, and the last EFM 6m to VK6 was 14 mins prior, quite weak at -26 dB.
Another thing to note was that from midnight to 6am that 6m WSPR had good paths happening, I had a path with VK8RH all night, and was still there at 6am. So the MUF was raised through the night which is a good predictor of high MUF during the day.
Edit- oh and congratulations to Nigel VK6CPU and Allan VK2EFM for this path. VK6CPU/p is actually a remote station at Albany set up by Rob VK6LD by the way.
Leigh VK2KRR"
Analysis... Just to add to the available info, there was only one spot for the opening between VK2EFM and VK6CPU/P and this is it...
Local (y-m-d)TXtxGridRXrxGridMHzWSNRdriftkm 2022-12-24 05:24VK2EFMQF56oqVK6CPU/POF84xx144.49047810-2003051
This is the predicted tropo map from F5LEN...
It suggests that there were reasonable tropo conditions on 144 MHz across the Great Australian Bight. This would account for signals going 1800kms from the SW corner of Australia to Adelaide but what about the remaining 1200kms or so from Adelaide to Sydney?
I suspect it was probably a Sporadic-E opening from Sydney and then a tropo duct across the Bight but it's impossible to be sure.
A similar opening to this happened back on the 15th Dec 2020 as outlined in this previous post HERE
Links..
1) More examples of long distance paths on 2m can be found on my 144 MHz page
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.
Back in the first half of 2022, I was following the progress of what was termed the 'ICOM SHF Project'. ICOM first announced this in December of 2021 and it suggested that they were developing a transceiver for the 2.4 GHz and 5.6 GHz microwave bands. See my earlier post HERE.
The blog post got a good deal of traffic and it was obvious that a lot of people were interested in this product even if was supposed to be for only two microwave bands.
I don't think many people had an idea earlier in the year just what ICOM had in the pipeline and it turned out to be pretty amazing.
In this post, I'll look at the new IC-905 in two parts. The first part is a summary and if anyone wants to look at the finer detail, that will be in the second half of this post further down.
In a future post, I'll look at the 10 GHz system.
Part 1 - The ICOM IC-905 in summary
The ICOM IC-905
At the Tokyo Hamfair in August of 2022, ICOM announced their new IC-905 radio which covers the following bands... 144 MHz (2m) 432 MHz (70cms) 1296 MHz (23cms) 2.4 GHz (13cms) 5.6 GHz (6cms)
They also have an optional transverter for 10 GHz (3cms).
As you can see from the photo above, it does have a similar appearance to the current IC-705 model which covers all of the HF, 6m, 2m & 70cms bands.
Note however that there is no RF in this part of the IC-905, it's just the control unit. The radio itself or at least the RF part of it is in the head unit which goes up next to the antenna.
This is part of the concept of putting the control unit indoors where the user is and putting the radio (RF) section up at the antenna. The 'LAN Cable' connecting the two will use PoE (Power over Ethernet) which will carry power and control signals up to the RF module as well as transferring the signals from the radio back down to the controller.
The main point here is to eliminate losses from coaxial cables running from the radio shack to the antenna. These can be really high at UHF and Microwave frequencies.
Some features of the IC-905 system...
1) The power output is 10-watts on 144 MHz, 432 MHz and 1296 MHz from a single N-Type connector. There is a separate SMA type connector for 2.4 GHz and 5.6 GHz and the power on those bands is 2-watts.
2) The controller has a 4.3 inch (11cm) colour display and as you might expect, a real time spectrum scope and waterfall display.
3) All the usual analogue modes like FM, SSB & CW as well as the D-Star digital mode which is standard for an ICOM radio.
4) One nice feature is ATV (Amateur TV) in FM mode.
5) One feature of huge importance is that the RF module will be frequency locked by GPS. This is a major shortcoming in several of the existing ICOM rigs on the market in that frequency drift on some digital modes on the UHF bands is a major problem. The GPS locking should help resolve this.
Price & Availability...
As of November 2022, ICOM have not announced a price for the IC-905. I suspect it will be in the $2000-$2800 price range but we'll have to wait and see.
As for availability, they haven't announced it. I suspect it will be the second half of 2023 before we see any units for sale.
Game Changer...
When ICOM released their IC-705 radio, there was huge interest in it despite it being a low power 10-watt radio. One of the key selling points is that it was a 'shack in a box' with all of the bands from 1.8 MHz to 432 MHz in one unit.
In a similar vein, the new IC-905 is very much a 'shack in a box' for the VHF bands and above. If ICOM had announced a new VHF/UHF radio with just 144 MHz, 432 MHz & 1296 MHz, there would be a lot of interest in it. The fact the IC-905 has 2.4 GHz and 5.6 GHz as well is pretty amazing.
I suspect the biggest change will be to the 1296 MHz or 23cms band. There is a serious lack of radios available for this microwave band and getting a separate radio for just one band is prohibitive.
Close up of the base of the Diamond X6000A
I can see a LOT of people buying Tri-Band type verticals made by the like of Diamond and Comet and using them with the new IC-905. I think it's going to generate a lot of activity on the 23cms band in urban areas in many parts of the world.
The thing about a radio like this is that it is really versatile. People may come up with new ways of using it that we haven't considered at the moment.
I can really see this radio being a game changer for the UHF and low microwave bands IF the price isn't too high.
***
Part 2 - The ICOM IC-905 in more detail
IC-905 Controller... Let's have a look at this is a bit more detail.
The image above shows the front of the IC-905 and you get some idea of the depth as well.
The photo above is of the front of the controller from the Toyko Hamfair last August.
The photo above shows the rear of the controller and again, you get some idea of the depth.
As you can see from the photo above, there is very little on the rear of the controller other than two heatsinks.
While the IC-905 uses a 12-volt supply, it seems likely that there is a much higher voltage going up the Power over Ethernet cable to the RF unit. It's likely that there is some type of switch mode power supply in the controller to generate this higher voltage and a reasonable heatsink is required for that. There are of course all of the low voltage supplies to all of the electronics in the controller as well and again, a heat sink aids in keeping things cool.
The image above shows the right hand side of the controller.
The image above shows the right hand side in more detail. The port with the Green LED and the cable in it is the Power over Ethernet cable that goes to the RF module.
The image above shows the left side of the controller with the various ports.
The photo above is an actual photo of the left side of the controller.
And now onto the RF module. This image above gives an overview of the underside of the RF module. From left to right...
a) The cable on the left is Power over Ethernet LAN cable from the controller unit.
b) The BNC socket has an RF output at 10 MHz which is controlled by a GPS unit inside the RF module. The 10 MHz signal reference from here is fed to the optional 10-GHz transverter and provides that unit with a stable frequency reference.
c) The connector on the right is for the CX-10G which is the optional 10 GHz transverter.
This image above is another view of the underside of the RF module.
The image above is the top side of the RF module. All 2m, 70cms & 23cms signals are fed out via one N-type socket. Both the 2.4 GHz and 5.6 GHz bands have their own individual SMA socket. There is also a SMA socket for a small whip antenna for to receive GPS signals.
The image above gives another view of the top side of the RF module.
The image above shows the top side with the GPS antenna connected.
The image above is an actual photo of the RF module on display at the Tokyo Hamfair.
If we consider that a N-type connector is about 2cms in diameter then the dimensions of the RF module above is about 18cms across and 26cms in height. The depth is perhaps in the region of 8cms.
In terms of operation, the new IC-905 is basically the same as the popular IC-705.
This image above is a screenshot from the controller showing it operating on the 5.6 GHz band with a selection of modes.
The image above is a screenshot of the 11cm display showing a selection of menu items.
One amazing feature of this radio is it's ability to use ATV (Amateur TeleVision). In the above image, you can see a received ATV signal inset in the screen.
And this is the received signal on full screen.
ICOM also intend to sell omni-directional antennas for both the 2.4 GHz and 5.6 GHz bands.
I suspect third party antennas for these bands will be a lot cheaper.
Video... and finally, this is the promotional video from ICOM for the IC-905
That's it. I've done my best to collate all of the information available and put it in one spot. We'll just have to wait now until ICOM announce a release date and price.
Addendum 25th Dec 2022... At a recent presentation, ICOM had this slide which showed the frequency stability of the new IC-905 versus the old IC-9700.
The IC-9700 which was released in 2019 and is a VHF/UHF transceiver covering 2m, 70cms and 23cms. It is not frequency disciplined by an external source and as can be seen from the chart on the left, it can drift hundreds of Hz with a change in temperature on the 23cms band.
This isn't an issue on say FM, D-Star, SSB or CW but it is on the very weak signal modes like FT8 or WSPR where a high level of frequency stability is required. This has led to some third party providers providing frequency stability solutions.
The chart on the right by contrast is that of the IC-905 at roughly four times the RF frequency. The IC-905 which is frequency stabilised by GPS only drifts a few Hz with changes in temperature.
This really is a game changer for all the VHF, UHF and SHF bands as frequency stability is now essential for very weal signal modes.
It was announced this week that the Irish trans-Atlantic 144 MHz beacon EI2DKH has ceased transmissions.
Operated on behalf of the Irish Radio Transmitters Society (IRTS) by Tony Baldwin, EI8JK, the EI2DKH beacon transmitted JT65B on 144.488 MHz with a CW identification on every even minute.
The beacon was established in early 2015 with the hope that the 2m signal would be heard across the North Atlantic in either Canada or the United States.
The beacon’s power output was 75 W to an array of 5 element Yagis at 60 meters above mean sea level and beaming due west from Sheeps Head in IO51dn.
As can be seen from the map, this was in the far south-west of Ireland and just over 3,000 kms from Newfoundland, Canada.
In its seven years of operating, there were no 2m reports from across the Atlantic.
In a statement on the 5th of May 2022, the beacon keeper Tony, EI8JK wrote...
"It has been pointed out that my EI2DKH beacon is perhaps not the best site. That coupled with the electricity cost for running it 24/7, I have decided to not run the Trans-Atlantic beacon this year.
If there is an EI/GI amateur with a good site on the west coast who would like to take it over, I would willingly supply the 4 antennas, splitter and pre-amp.
Sorry to disappoint.
73, Tony, EI8JK."
This project might be of interest to any individual or group who have access to a site which is near the western seaboard of Ireland and has an extremely low horizon to the west-north-west.
In 2017, the Northern Black Forest Group DR9A in Germany won the multi-op section in the IARU Region 1 2m contest. This is held in September every year.
The photo above shows the 144 MHz antenna system. Lower down on the mast, there are 4 high stacks of medium gain 6-element Yagi's pointing in fixed directions every 45 degrees. At top of the mast, there is an array of 4 high gain 17-element Yagi's for when more gain in a particular direction is needed.
These are the top 20 stations in the results...
The DR9A contest station operated from the JN48EQ in the south-west corner of Germany. As you can see from the map below, it is pretty much in the centre of western Europe with stations in all directions.
The short video below gives a flavour of what the contest was like...
9th February 2022: There was another TEP (Trans-Equatorial Propagation) opening on 144 MHz between the Caribbean and South America but this time, it was a bit unusual.
As the map above shows, nearly all of the signals shown on the PSK Reporter website were from Argentina to Aruba, Bonaire, Curacao and the Dominican Republic. There was also some from Argentina to Puerto Rico. What was unusual was the lack of signals further east from Puerto Rico to the south of Brazil.
Usually there are two parallel TEP paths crossing the Geomagnetic Equator. For whatever reason, the eastern path to Brazil seems to have been mostly absent.
Spots on the DX Cluster show a small bit of activity from Puerto Rico to Brazil but it seems to have been at a very low level compared to the path further west.
Spotter Freq. DX Time Info Country NP4BM-@ 144180.0 LU2EPO 01:03 09 Feb tnks tep q65b qso Argentina NP4BM-@ 144180.0 LW2DAF 01:01 09 Feb tnks tep q65b qso Argentina PY5EK 144180.0 WP3DN 23:53 08 Feb Q65B -9 dB 994 Hz TNX TEP Puerto Rico
The path from PY5EK in Brazil to WP3DN in Puerto Rico was the only one I noticed on the PSK Reporter website.
As for why the western TEP path was better than the eastern TEP path???
144 MHz Report... Martin, PJ4MM in Bonaire reports working the following stations in Argentina...
At the moment, there seems to be an TEP opening on the 144 MHz band every evening between South America and the Caribbean area. The evening of the 6th of February was no exception with an opening just after midnight UTC on the 7th (~8pm for the stations involved on the evening of the 6th).
Brett, PJ2BR in Curacao reports working stations in Argentina with just 10-watts into a 3-element Yagi!
PJ2BR writes... "This is an unusual evening. Was able to work @LU4DJC, @LU1FAM and @LU2EPO on 2m Q65. What makes this unusual is, made the contact with 10W and a 3 element Arrow yagi! My signal was also rx’ed in Uruguay. 5461 Km on 2m 10W!"
Many people will be familiar with the Arrow dual band antenna which is often used to work the satellites.
5,461 kms on 144 MHz with just 10-watts in to a 3 element Yagi is pretty amazing. Remember that this is via Trans-Equatorial Propagation and not via some satellite passing over.
It is also a LOT further than the 3000kms or so across the North Atlantic from Newfoundland to Ireland which has never been bridged on 144 MHz.
To complete the contact, PJ2BR was using the Q65 digital mode...
In this screen shot, LU2EPO in Argentina was hearing PJ2BR at -16dB which is just below what is detectable by ear.
There are the spots from the DX-Cluster for the opening...
Spotter Freq. DX Time Info Country PY2OAL 144180.0 FG8OJ 01:47 07 Feb TEP 4300 KM tnx Q65 Sent: -05 Guadeloupe PY2SRB-@ 144180.0 FG8OJ 01:21 07 Feb Q65b CQ Guadeloupe PY2SRB-@ 144180.0 NP4BM 01:20 07 Feb Q65b CQ Puerto Rico HI8GSP-@ 144180.0 LU2EPO 01:14 07 Feb Q65 TNX FOR THE CONTACT Argentina PY5EK 144180.0 WP4KJJ 00:57 07 Feb Q65B +0 dB 1529 Hz TNX TEP Puerto Rico PY2SRB 144180.0 WP4KJJ 00:53 07 Feb Q65B -1 dB 1555 Hz Puerto Rico LU1FAM-@ 144180.0 PJ4GR 00:50 07 Feb Q65B Bonaire LU1FAM-@ 144180.0 HI8CAF 00:49 07 Feb Q65b Dominican Republic LU1FAM-@ 144180.0 PJ2BR/QRP 00:49 07 Feb q65b Curacao WP4KJJ-@ 144180.0 PY5EK 00:49 07 Feb Brazil WP4KJJ-@ 144180.0 LU2EPO 00:48 07 Feb Argentina LU4DJC-@ 144180.0 PJ2BR 00:41 07 Feb TEP Q65B Curacao LU4DJC-@ 144180.0 HI8CAF 00:40 07 Feb TEP Q65B Dominican Republic LU4DJC-@ 144180.0 HI3I 00:37 07 Feb TEP Q65B Dominican Republic PY2SRB-@ 144180.0 WP3DN 00:31 07 Feb Q65B -8 cq Puerto Rico
Links...
1) For more examples of long distance openings on the 2m band, see my 144 MHz page.
