You might check with the https://hamwan.org folks, they have experience with long haul links over the Salish sea. On Thu, Sep 9, 2021, 05:43 Toussaint OTTAVI via 44Net < 44net(a)mailman.ampr.org&gt; wrote: _________________________________________ 44Net mailing list 44Net(a)mailman.ampr.org https://mailman.ampr.org/mailman/listinfo/44net

The problem, as I see it, would not only be signal strength, but also overcoming the curvature of the earth with suitably high antennae on both ends

Having two links with monitoring and metrics may be an interesting tool for propagation checking :-) We must also set up routing priorities in relation with link quality. But that's another topic :-)

Anyway, that's what I was fearing : we are in the SHF domain, we cant' just put some UBNT stuff on the highest point and see if it works, but we need real SHF experts in the team.

Having two links with monitoring and metrics may be an interesting tool for propagation checking :-) We must also set up routing priorities in relation with link quality. But that's another topic :-)

Anyway, that's what I was fearing : we are in the SHF domain, we cant' just put some UBNT stuff on the highest point and see if it works, but we need real SHF experts in the team.

There used to be a few (PTT&military) links between Corsica & continental France, some as early as 1947[0,1], although way down around 100MHz[1].

Those areas have a huge advantage of having somewhat high mountains not that far from the sea. Quickly looking at radiomobile, there seems to be around 154dB of free space loss between Grasse (Le Haut Montet, alt 1330m) and Calenzana (Monte Grosso, alt 1900m) for a distance of 210km, with no obstruction from the curvature of earth.

Ciao Toussaint, first of all, sorry for being late in my answer. I was involved in the working group who established the record of 304 km during the first experiments in the first months of 2007 (https://www.cisar.it/index.php?option=com_content&view=article&id=3…) and then improved the bandwidth of the original link with the collaboration of a notorious brand in the 2016 (https://en.wikipedia.org/wiki/Long-range_Wi-Fi#Italy) If you like, please consider both myself as first point of contact for old memories and Gian Leonardo Solazzi IW2NKE as coordinator of nowadays WiFi working group of Italian CISAR association if you have any specific question about our unforgettable and wonderful experience about the WiFi longest ham radio world record. Ciao from Italy. IW0SAB Renzo Rossi > Il 09/09/2021 14:41 Toussaint OTTAVI via 44Net &lt;44net(a)mailman.ampr.org&gt; ha scritto: > > > Hi all, > > Some friends from south of France submitted the idea of a 5 GHz link > between France and Corsica. The distance is 200-250 km, mostly over the > sea. It's far longer than what I could see on HamNetDB, for example. But > it's shorter than WiFi world records (some of them attempted more than > 10 years ago between Italy and Sardinia). I never attempted links longer > than 40km, so I don't have any experience. And we don't have any SHF > expert locally... > > 1/ Do you think a permanent and stable 250 km link over the > Mediterranean sea is doable ? Are some of you using such long links in 5 > GHz ? If so, could you share your technical experience here ? > > 2/ Are there any people from Italy on this list ? Are there any > volunteers between Genova and Roma to attempt a link with the East coast > of Corsica ? If it works, would there be  an interest in establishing a > permanent link ? > > Thank you for your comments, > > 73 de TK1BI > _________________________________________ > 44Net mailing list > 44Net(a)mailman.ampr.org > https://mailman.ampr.org/mailman/listinfo/44net

I was involved in the working group who established the record of 304 km during the first experiments in the first months of 2007 (https://www.cisar.it/index.php?option=com_content&view=article&id=3…)