The Ultimate Guide to Affordable NVIS Comms (How to Build a Regional Off-Grid Radio Box)

Comments

• itsathursday@lemmy.world ⁨7⁩ ⁨hours⁩ ago

  Anyone know how this compares to the mesh network?

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  • ProdigalFrog@slrpnk.net ⁨6⁩ ⁨hours⁩ ago

    If by Mesh Network you mean Meshtastic, they have very different use-cases.

    Meshtastic is requires regular nodes/repeaters within its somewhat smaller effective range to be effective (putting repeater stations atop hills or mountains can drastically extend that effective range), it also exclusively operates via text, not audio.

    NVIS is just a small long-range portable radio that bounces radio waves directly off the ionosphere which is reflected in a circular radius from the antenna of 150 to 300 miles, and is not reliant on being atop mountains to attain that range due to the reflected bouncing. The video gives details on how it is generally used.

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• perestroika@slrpnk.net ⁨19⁩ ⁨hours⁩ ago

  Thanks for dropping the abbreviation. :) For those who want text:

  en.wikipedia.org/…/Near_vertical_incidence_skywav…

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• poVoq@slrpnk.net ⁨17⁩ ⁨hours⁩ ago

  Linking this with some sound modem to transmit text data, ideally with some automatic repetition to remove errors, will probably be much nicer to communicate with. But cool concept overall.

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  • perestroika@slrpnk.net ⁨6⁩ ⁨hours⁩ ago

    What makes me worry is the size of the “reflector”. I wonder what symbol rate it is possible to get if the “reflector” is literally everywhere above you - the time delay between start of reflection and end of reflection might be considerable.

    I found a resource with practical advise about using NVIS, including using meteorological data (ionograms) to determine the best frequency, antenna diagrams and such.

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