VIC design session v52: reasoning

Lab note — sub-1mH choke sweep, VIC resonant tank

This sweep was supposed to walk f_r down toward the 1–100kHz band by dropping per-choke inductance into the 0.2–1.0mH window. It didn't do that. Every surviving top candidate pinned at the floor — 0.1mH per choke, 0.2mH total — and parked at f_r = 303.9kHz, still 3× above the practical ceiling. So the honest result: pushing inductance DOWN to chase harder film ignition pushes frequency the WRONG way. With C_eff fixed at 1.37nF, you cannot both light the vapor film hard and land in-band by shrinking L alone; the two levers fight.

What the sweep does show cleanly is a Q-vs-wire tradeoff at fixed geometry. Going AWG24→28 and 50→100 turns trades coil Q (240→88) for series resistance, which pulls tank Q (24.4→20.8), cell voltage (293→249V), and film field (117→99 Td). Every candidate still lands INSIDE the 80–250 Td / 3–6 eV cold-chemistry window — that part is robust. Current restriction stays weak: 650–770mA series current is high, not the sub-amp displacement-dominated regime I want, even at 96.5% displacement current.

I'm adopting #1: highest Td (117), best coil Q (240.9), lowest AC R, hardest ignition. I accept the frequency violation as a flagged, known defect rather than pretend it's buildable as-is.

Next session: the only way in-band is to RAISE C_eff — more cells in parallel or larger electrode area — so I can keep L modest AND drop f_r. Sweep cell count 8→24 and tube length 25→75mm against the same Td target.