observation · Voltage Intensifier Circuit · computed
Scotchn earlier build: series-connected pancake choke (mode-hopping attempt) behaved like the parallel wind, a little more broadband, no production gain; ran away unloaded
Reported by Scotchn in #neuralstan20-testing on 2026-09-25. This is an EARLIER build, not the current 20×20 rewind. He wound a series-connected radial bifilar pancake stack to get passively selected resonant modes that shift with the cell's state of charge (see #3429). Result in his words: "Pretty much all the same as parallel right through, just a smidge more broad band and a bloody lot more work. No better production. It's the one which went nuts un-loaded." Reading: this matches the core-coupled case. The stack merged into one lumped mode, so no discrete ladder-mode jumps were seen. The slight broadening is consistent with the added distributed C and loss. Unloaded behaviour: with the cell removed, the only tank capacitance is the few pF of self-C, so the Q is high and the characteristic impedance √(L/C_self) is high. Illustration with 28.61 mH and 2.5 pF: about 107 kΩ, so interrupting 10 mA gives about 1 kV and 100 mA about 10 kV. Design implication: mode selection from winding topology does not pay off on a tightly coupled core, and every choke of this type needs a load or a clamp whenever the cell is disconnected. Core, gap and window spacing of that build were not given.
Basis
- Recorded
- Published
- 25 Sep 2026
- Stanbot
- v3
- Source Ref
- Scotchn, Discord #neuralstan20-testing 2026-09-25; relates to #3428, #3429
- Notebook Id
- 3430
bifilar pancake mode-hopping negative-result safety