My first guess would be that those nodes had a poor GPS lock and are actually much closer. Unless you've received multiple reports from them where the location is about the same (better if it changes a little bit so you know they're not just retransmitting the same inaccurate position because they can't get a good GPS lock), in which case some spooky rf stuff is probably happening.
this post was submitted on 31 Jan 2025
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A lot of them are now saying unrecognized.
How about a node in an airplane. I've gotten crazy long contacts via airplane hop.
That is a possibility.
According to the docs, this would be a new distance record.
No, because it was relayed over the mesh, not direct. If it were direct, then it absolutely would be a new distance record.
Sounds like ducting, what band are you operating in? what's the terrain like between you and the transmitters? What are the weather conditions like? Was it a similar time of day?
Terrain is generally quite flat between me and all the received nodes and it only happens at night. So ducting may be possible because the ocean is quite nearby on both the transmitter side and the receiver. I initially dismissed ducting just because of the fact that it's January and four in the morning.
Edit: band 33cm (907mhz)
With a powerful enough antenna and line of sight its not impossible. But still that's impressive
Since this is meshtastic, it's definitely a very low-powered device.
I'm saying the other party may have such an antenna
Yeah, that's possible. I would have no idea.
Ionosphere?
I didn't think the ionosphere would affect radio signals in such a high frequency range. I know that HF signals reflect off the ionosphere at less than 30 megahertz, but I thought 915 would just punch straight through.
That's a good point, but the only getting the messages at night lines up with previous reporting on ionosphere bouncing.
220 miles is not direct line of sight, at that point you have to bounce off of something
I dismissed it last night as an artifact because it was only one single node. But tonight I can't dismiss it because it's three of them. And they all show as either two or three hops away.
Edit: I stand corrected. They are between 270 and 320 miles away. And I thought it might have something to do with a heat inversion, but it's the middle of January. I wouldn't think that would be the cause.