[HamWAN PSDR] Thanks. Maybe I could explore local HamWAN coverage (Was: Need help near Bellingham, WA?)

Steve Stroh steve.stroh at gmail.com
Tue Jul 13 16:45:57 PDT 2021


I understand and agree with PSDR's focus on "core mission of building
and supporting the high speed backbone and access". That's a noble and
challenging mission that requires focus.

But it's inaccurate to dismiss systems that use lower frequency
spectrum such as 440-450 MHz as merely "1200/9600 AX.25" as the best
that can be done. One example is VARA FM which can do 25 kbps in a
conventional 20 kHz VHF / UHF radio channel. Yes, there are issues
such as it being proprietary, requires Windows, payment of a license
key for best performance, etc. But it works, and performance is FAR
better than "1200/9600 AX.25".

It's also inaccurate to dismiss all systems that operate in 902-928
systems as "performance as abysmal" due to "interference is
prevalent". For example, one vendor of robust systems for 902-928 MHz
is FreeWave Technologies, whose key technology is Frequency Hopping
Spread Spectrum (FHSS). It's slower, but FHSS is far more robust than
DSSS that Wireless ISP systems that operate in 902-928 MHz that do
operate poorly in the presence of congestion.

Thanks,

Steve N8GNJ

On Mon, Jul 12, 2021 at 2:44 PM Nigel Vander Houwen <nigel at nigelvh.com> wrote:
>
> Kingsley, and others,
>
> Since it was brought up, I’ll add a quick note here. Trees in the path has been a known hiccup that we’ve hoped for a magic resolution to, but one has not been forthcoming. We did some testing with 900MHz radios, but interference there is prevalent, and performance was abysmal. We chose not to purse that thread further.
>
> One could potentially build a relay, but operating on the lower bands means bandwidth restrictions by rules, and by competition for spectrum. You’d be effectively tying 1200/9600 AX.25 to the network. Folks are of course welcome to do so, but in terms of HamWAN itself doing it, that feels to me like reinventing the wheel, and I believe that gets too in the weeds away from our core mission of building and supporting the high speed backbone and access.
>
> So, trees and such remains on our minds, but currently without any good solutions that are performant, and align with HamWAN’s goals.
>
> Thanks,
> Nigel

-- 
Steve Stroh (personal / general): stevestroh at gmail.com


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