I think this should have a topic:
www.youtube.com/watch?v=D5WuObCX31ESchematic:
https://i.imgur.io/P9kZ2bj_d.webp?maxwidth=640&shape=thumb&fidelity=mediumDescription:
The original circuit is built with two separate modules (one transistor pair for one bifilar coil). Then connecting the two modules in parallel to the 12v battery.
Or it can be build on one board. Half of the circuit is the same (separated by the dashed lines), but twisted upsidedown to connect it parallel.
Stator coils are bifilar 120° degree Air core D coils (not 180° degree!). The impedance resistance of the coils are 12.1 ohms (Ω) with 23 AWG / 0.573mm wire, for each four coils. Measured separately.
Rotor has 4 neodymium magnets North, South, North and South arrangement (N, S, N & S). They need to pass the straight sections of the D coils when spinning.
The PNP transistor is MJL21193.
The NPN transistor is MJL21194.
Optional amplifier transistor pairs might be TIP42 & TIP3055, or MN2488 & MP1620.
Resistors are 1k / 5w, for 12v battery. Or 2.2k / 5w for 18v, 3.9k for 24v, 8k for 30v, 9k (8k or 10k) for 36v, 12k for 42v and 16k (15k) for 48v, etc. The resistor is used for protecting the transistors.
Diodes are SR5100. It's possible to use bridge rectifier too. 1N4007 might also work. Ultra fast UF4007, or MUR460 are most likely better.
The neon indicator is used for protecting the transistors from high voltage spikes.
Battery used for the demonstration is small 12v lead acid chemistry. Bigger battery or different chemistry might cause issues, cause of the different natural resonance.
Power consumption peak is 4.4w and under 4w when the system is stabilized.
Note: The circuit might work better with Low pass filter (Pi / EMI / CLC) to charge capacitor. Rather than the voltage spikes straight to the battery.
Credits:
All credits for creating this circuit and coil design goes to Jorge Rebolledo aka ”Skycollection” channel on YouTube.