{"id": "card_n_73d989606f90", "kind": "note", "title": "Radio-wave production — the chain leaves the bench", "body": "Drive an antenna with the oscillator and the wave departs at c: λ = c/f — sealed:\nthe 1.591 MHz LC wave is ≈ 188 m long (floor(c·2π·10⁻⁷) = 188): https://narrowhighway.com/s/1ee0d3ed486453eee0967146a531984888709198b39fb16a7b2c2a5f58ef1b73 . A half-wave dipole\nfor it spans ~94 m — which is why AM stations use towers and crystal radios use long wires.\nScale the cavity up from the bench to the planet and the same physics is the Schumann\nresonance: lightning the oscillator, the Earth-ionosphere gap the tuned circuit.", "source": {"label": "Concordance assay — 2026-07-09", "url": "https://narrowhighway.com/s/1ee0d3ed486453eee0967146a531984888709198b39fb16a7b2c2a5f58ef1b73", "ref": "electronics_dig", "authority_tier": "engine_derived"}, "shelf": "science", "box": "electronics", "bands": ["radio waves", "antenna", "wavelength", "electronics", "transmission", "dipole"], "connections": [], "author": "engine", "created_at": "2026-07-10T00:59:49.508624+00:00", "updated_at": "2026-07-10T00:59:49.508624+00:00", "visibility": "public", "lifecycle_stage": "public", "volatility": "permanent", "surface": "secular", "metrics": {"paperclips_count": 0, "helpful_count": 0, "not_helpful_count": 0, "cite_count": 0, "walks_through_count": 0, "flagged_count": 0}, "source_hash": "507fb9aa45cdb427ec17a5673de6bf056077debf0d460581539664e3c64703f6"}