QUORUM · PROBES

Attendance without location, without biometrics, without hardware. Open the same page on two phones — one transmits, one listens.

Probe 02 · token decode

Emits a hopping token and measures whether a detector can actually read it — per-symbol margin, symbol error rate, and token decode rate against capture time. Adjustable dwell, because dwell length is the open question. Run this one.

Probe 01 · ultrasonic viability · complete

Sweeps 16–22 kHz and reports the raw response. Answered its question on 2026-07-27: a cheap Android captures cleanly at 48 kHz, 19.5 kHz is the strongest inaudible carrier, and the room response is a comb rather than a smooth rolloff. Kept for reference.