Radioactive Decay Powers Experimental Bitcoin Seed Generator

A novel open-source project called Entropy32 Plus uses radioactive decay as a physical entropy source to generate Bitcoin BIP39 seed phrases. The device, described as an experimental and educational tool, collects pulses from a Geiger counter and measures the time between detected events.

The team's firmware converts comparisons between consecutive intervals into bits, collecting 512 comparison bits before processing the data with SHA-256. This process conditions the raw Bitcoin seed data and reduces visible patterns linked to detector dead time or count-rate changes.

The device then formats part of the resulting hash as a standard BIP39 recovery phrase using the first 16 bytes for a 12-word phrase or all 32 bytes for a 24-word phrase. Entropy32 Plus's open-source design includes firmware, circuit-board designs, fabrication files, and printable enclosures.