The main entropy source is generated from the jitter measurement of 3 ring oscillators. Pair of DIP20 sockets to house a pair of 74’240 or 74’540 inverting buffers with the ring formed across both devices. Randomly mismatched buffers, especially cheap questionable re-marked chips from AliExpress would make every device unique.
One 3-stage ring oscillator, one 5-stage, and one 7-stage, will use up all but one pin of two 8-bit buffers, and provide a nice variety of output.
Using the internal (inaccurate) oscillator for jitter measurement would also vary entropy between devices. And because the ring oscillators are all different lengths, could also measure beat frequency between them to add more entropy.
🔪 Joel May-Kill 🔪
npub1m3…k4xuv
2026-09-17 00:05:19 UTC
in reply to nevent1q…rqqf
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npub1m33czg27v449dkq5jh80qg9q52gumjcpj5uchh0d250w8yudmxsqmk4xuvSeen on
wss://relay.momostr.pinkPublished at
2026-09-17 00:05:19 UTCEvent JSON
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