Cave-Link: Underground text communication system

Re:Cave-Link: Underground text communication system by dll on Wednesday November 10, 2021 @07:37AM (#29173973)

I wonder how the licensing issue referenced in the Wikipedia article is handled in the UK. I imagine Ofcom will have had to approve and license these installations, or will they have made these exempt (I can't find any evidence of this)?

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Re:Cave-Link: Underground text communication system by gnfargbl on Wednesday November 10, 2021 @09:13AM (#29174818)

I can't see these devices specifically mentioned in https://www.ofcom.org.uk/__data/assets/pdf_file/0028/84970/i..., though the frequency range they operate in (20-140kHz) is allowed to be used by induction loop type applications, at a suitably low power.

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Re:Cave-Link: Underground text communication system by ale42 on Wednesday November 10, 2021 @09:22AM (#29174896)

... but the cave link uses relatively high power levels (20-30 Watts if I remember correctly)

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Re:Cave-Link: Underground text communication system by lazide on Wednesday November 10, 2021 @09:52AM (#29175195)

Inductive stove tops are also In the KW range

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Re:Cave-Link: Underground text communication system by detaro on Wednesday November 10, 2021 @09:09AM (#29174775)

as far as I know similar general licensing exists for such purposes. Lots of inductive applications need it.

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