Showing posts with label LU5FF. Show all posts
Showing posts with label LU5FF. Show all posts

Sunday, February 5, 2023

4853km TEP opening at 432 MHz reported from Curacao to Argentina - 5th Feb 2023


Brett, PJ2BR in Curacao in the Caribbean reports that on the 5th of February 2023 (01:18 UTC), his 432 MHz signal were heard by Javi, LU5FF in Argentina by Trans-Equatorial Propagation (TEP). The distance was 4853 kms!

This really is ground breaking news (*). It was only on the 4th of February that I put up a post about what was up to then the only 432 MHz reception report via TEP in South America and that was from 1978. I tagged PJ2BR on Twitter about the post and a few hours later, we have a second 70cms TEP report!


The Green exchange is for 144 MHz while the Yellow is for 432 MHz (*).

Proof of Concept (*)... For this TEP opening on 432 MHz, PJ2BR was using the Q65b weak signal mode. This is significant because it means that modern digital weak signal modes can be used for TEP openings at 70cms. It's not a case of there being too much doppler or spreading of the signal that only CW can be used. This would likely require a much stronger signal for a contact to be made.

For the record, here is a screen grab off the PSK Reporter website before it disappears.


Let's hope that this news will encourage more stations in the Caribbean and in South America to try to make a TEP contact on the 432 MHz.

(*) = Caveat... Someone raised the question if the reports on 432 MHz are genuine? They do after all follow some Q65 reports on 144 MHz and they wonder if it's the software generating these 70cms reports?

It's a bit like conducting a science experiment and we have one data point, not exactly the five-sigma required for a definitive conclusion. What we need are more stations in South America and the Caribbean to test the TEP path on 432 MHz. If there are no more reception reports then it raises some question mark over this new report. If there are more reports then it means this report was probably ok.

Addendum: 6th February 2023... There was another TEP 'reception report' on 432 MHz on the 6th of February 2023. This time it was from WP4KJJ in Puerto Rico to LU9FVS in Argentina.


I believe the stations involved have concerns about the software generating incorrect reports after the band has been changed.

I suspect what is required is the reception of a good old fashioned CW signal to eliminate any software issues.

Wednesday, May 18, 2022

Opening on the 40 MHz band between Slovenia & South America - 16th May 2022


Borut, S50B in Slovenia reports that on the 16th of May 2022, his FT8 signal on 40.680 MHz was heard for the first time in South America!

The map above shows the path from S50B to PY2XB in Brazil (~10,000kms) and LU5FF in Argentina (~11,300kms).

Borut's 40 MHz was also heard by EA8BFK in the Canary Islands (3095kms) on the 11th and the 17th of May.  I don't know if the path to EA8 was open on the 16th but it does suggest the F2 layer propagation might be reaching as high as the 40 MHz band on north-south paths on a regular basis.

As there have been reports of recent openings on the higher 50 MHz band from Europe to South America, it should be no great surprise that there was an opening on the lower 40 MHz band.

I'd suggest however that this shows how valuable the 40 MHz band is to radio amateurs and to those interested in propagation research. Signals on the 40 MHz band give an early warning of potential openings on 50 MHz as the Maximum Usable Frequency (MUF) will often be just below 50 MHz. If someone hears a 40 MHz signal then at least they know what direction an opening might be likely.

It's also good to see some of the radio amateurs in South America getting interest in the 40 MHz band. It will be interesting to see if they report on any openings to the experimental stations on the 40 MHz band in North America.

Links...

1) As always, plenty of info on my 40 MHz page.


Saturday, November 28, 2020

5400km TEP opening on 144 MHz between Argentina and the island of Aruba - Nov 2020

In two recent posts, I covered some recent 144 MHz TEP openings from Guadeloupe to Brazil during October 2020 and from  Curacao to Argentina in early November. 

P41E on the island of Aruba has been also been busy during the month of November 2020 and has worked several stations in Argentina via TEP.

One of the longest contacts was with LU2EPO with a claimed distance of an impressive 5449 kms.

In the graphic above, the geomagnetic equator is shown in Purple. Both P41E and the LU stations are equidistant from it and are also at right angles to it, both factors which are important at 144 MHz.


With Trans-Equatorial Propagation (TEP), zones of high ionization occur either side of the geomagnetic equator in the F layer of the ionosphere. What makes the mode so interesting is that it can allow propagation on the VHF bands from 50 MHz to 144 MHz. As the zones of ionization is roughly 400kms above ground level, the propagation paths achieved are in the region of 4000 to 5000 kms, much greater than what might be usual with Sporadic-E.

Here are a selection of videos showing the contacts made during the month of November 2020...

Contact with LU4FW on SSB...

Contact with LU3FCI and great to see the vintage Yaesu FT-480R in action! ...

Contact with LU3FCI...

P41E was using 100 watts into a 13-element Cushcraft Yagi.

* * *

Addendum: Thanks to Etienne, P41E for sending on the following information.

This is a photo of the antennas used for 144 MHz and 50 MHz


P41E is using an old an old Yaesu FT-767GX and a Tokyo HL160V running about 100 watts.


Etienne has very kindly sent on a log extract of what he has worked on 144 MHz from the 17th to the 28th of November 2020.


There are a total of 33 contacts in total. Looking through them, some are repeat contacts on different days or on a second mode. The log contains 17 separate stations from Argentina and most of these would have been in the 4500km plus range.


You will note that the majority of the contacts are on SSB with a few on FM and FT8.


Note also the times of the contacts which are around 00:00 to 02:00 UTC. This is around 21:00 to 23:00 for stations in Argentina and 20:00 to 22:00 for P41E in Aruba. This ties in well with Trans-Equatorial Propagation which is thought to peak at about 20:00 local time.

Solar Data... Just for reference purposes, I have included the solar data for the range of dates concerned...

#              Radio  SESC 
#              Flux  Sunspot
#  Date     10.7cm Number
2020 11 17   79     11
2020 11 18   77     11
2020 11 19   77     11
2020 11 20   82     11 
2020 11 21   85     23 
2020 11 22   88     35 
2020 11 23   96     38
2020 11 24  100     37
2020 11 25  104     40 
2020 11 26  106     43
2020 11 27  106     60
2020 11 28  110     67

Links...
a) I have a number of posts about long distance 144 MHz contacts on the blog and I 
keep a list of them here... https://ei7gl.blogspot.com/p/144-mhz.html