Dutch radio amateurs bounce 1299 MHz microwave signals off the planet Venus

On the 22nd of March 2025, a group of Dutch radio amateurs managed to successfully bounce a 23cms microwave signal off the planet Venus using the 25-metre Dwingeloo telescope.

At the time, Venus at the time was at its closest point to Earth with a distance of 42-million kilmetres. This happens approximately every 580 days which is about a year and seven months.

For the test, they used a 278 second long tone at a frequency of 1299.5 MHz. The return path from the Earth to Venus and back was about 280 seconds which is 4 minutes and 40 seconds. They repeated this cycle four times and a sample of the returned signal is shown below.

The test transmissions were also heard by another group using the 25m Stockert radio telescope in Germany.

They hope to resume their Earth-Venus-Earth (EVE) at the next closest approach in October of 2026.

Link... https://www.camras.nl/en/blog/2025/first-venus-bounce-with-the-dwingeloo-telescope/

Opening on the 40 MHz band between New Zealand and the UK - 16th March 2025

On the 16th of March 2025, there was an interesting opening on the 40 MHz (8m) band between New Zealand and the UK.

ZL28M is an 8m beacon on 40.680 MHz and is located on a hilltop on the North Island of New Zealand. It is operated by Mark, ZL2WHO and is running 10-watts into a 3-element Yagi beaming at the north of Australia which also the direction for the south of Europe. The beacon uses an RF ZERO controller and operates on FT8 and CW.

The beacon was received by Paul, G9PUV who is located in the south-east of England. The screenshot by Paul of the FT8 decodes is shown below.

Paul reports that he only got 3 decodes and that he was beaming in the general path of short path to New Zealand over the hills of the South Downs which have a 3-degree elevation.

The signals were in the region of -15dB to -19dB which means that they were weaker than what can be heard by the human ear. The time of 08:25 UTC is consistent with it being a short path opening.

Direct or skewed path??? As can be seen from map above, the direct short path from the UK to New Zealand goes well into the Arctic region. Did it really go that far north or was it skewed to a more southerly path where propagation on the low VHF bands might be more likely?

Whichever it was, it's always interesting to see such a long path like this on the 40 MHz band. At about 18810 kms, it's only about 1200 kms shy of the maximum of 20,000 before it changes to long path.

It also worth mentioning that there were some openings from New Zealand to Spain in the previous few weeks. On the 20th of February and the 12th of March 2025, Joan EA3ERE reported reception of the ZL28M FT8 beacon. The path to the south of Europe is a lot more favourable but is still a considerable distance at 19,467 kms.

Addendum: Rik, ON7YD reports that S57TW in Slovenia was recently copied by ZL2005SWL in New Zealand (RE68) on 40.680 MHz FT8 in the late afternoon. 8m was open to PY (Brazil) and CE (Chile) at that time, so it was most likely long path.

Additional info... Back on the 13th of March 2023, G9PUV and EI2IP in Ireland were heard by Bob, ZL1RS in New Zealand via long path. See previous post HERE

Also see my 40 MHz page... https://ei7gl.blogspot.com/p/40-mhz.html

VIDEO : Understanding VHF Propagation by Rohde & Schwarz

I recently came across a video on YouTube titled 'Understanding VHF Propagation' by Rohde & Schwarz, a company synonymous with high end RF and electronic test equipment.

It covers the myth of “line of sight” at VHF, tropo refraction, ducting, diffraction & scattering, Sporadic-E, meteor scatter and moonbounce.

It's a good primer on VHF propagation and covers in 43 minutes what might take a few hours to read in a book. It would be appropriate for anyone studying to get an amateur radio licence or just wants to get a basic understanding of how radio signals behave on the VHF bands. i.e. 50 MHz and above.

Video below...

New site found for Irish beacon network - March 2025

A few weeks back, I had a post up about how the EI1KNH, EI0SIX and EI4RF beacons in Ireland had to shut down due to a change of ownership of the beacon site. The good news is that a new site has now been found!

The new location is about 4kms to the south of the old site and it's a bit lower in altitude. It's certainly not as good as the old site but the challenge for any amateur radio beacon is to find any site where a beacon can operate.

The new site is nestled in the foothills of the Wicklow Mountain just to the south of Dublin and then local mountains and hills will certainly have a major impact in certain directions.

This is the approximate horizon of the new site...

To the north-east and on a heading of about 40 degrees, the Irish Sea is visible and there is a very good path to the Isle of Man and Scotland.

As we move further south, the local terrain starts to become more of an issue. The take off to the north of England is reasonable but once we go below a line say running from Liverpool to Leeds, it gets to be more challenging.

For example, the horizon in the direction of London and the south-east of England is about 6-degrees which will make reception difficult especially on tropo. 

To the south-west of Ireland which is in my direction here in Cork, the horizon is about 14 degrees which effectively kills all signals.

This map shows where tropo signals might be heard and the maximum range for one-hop Sporadic-E.

The range for single hop Sporadic-E to northern Europe is pretty good but the maximum range to Spain and Italy is shorter due to the mountains near the beacon site.

As of early March 2025, work in now progressing on the beacon and it is hoped that the beacons will be up and running in time for the start of the Sporadic-E season in mid to late April.

Due to the change in location, the EI1KNH beacons on 40.013 MHz and 60.013 MHz will be getting a new callsign. EI0SIX will return on 50.004 MHz while EI4RF will return on 70.013 MHz.

It is hoped that all four beacons will use FT8 as part of their transmission sequence which should help identification under weak signal conditions.

I'll put up another post once the beacons are operational.