TIL that Leon Theremin — inventor of the electronic instrument played without touch by the capacitance your hands create at different distances — also invented the first “passive” listening device, with no internal power supply, relying on energy beamed from an external source.
Podcast:
https://www.abc.net.au/listen/programs/no-one-saw-it-coming/the-great-seal/106590842
Leon Theremin: https://en.wikipedia.org/wiki/Leon_Theremin
The listening device:
https://en.wikipedia.org/wiki/The_Thing_(listening_device)
Greg Egan
npub1qq…j5nhv
2026-05-15 08:25:59 UTC
Author Public Key
npub1qqm7nu2qf25xd3mw6y6cyp4v2wr7ktf43ymp5wqz4u8jvz76ymtsjj5nhvSeen on
wss://relay.ditto.pubPublished at
2026-05-15 08:25:59 UTCEvent JSON
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