Vishay IRFP460 – Fast switching, ruggedized device design, low on-resistance and cost-effectiveness. The TO-247 package is preferred for commercial-industrial applications . 500V 20A device.
The transistors used in the prototype, and recommended for replications are the NTE2397. This is not a very common transistor in Europe at this time and so the popular IRF740 might perhaps be used as it appears to have all of the main characteristics of the NTE2397 transistor. ‘UFOpolitics’ suggests the 2SK2837 (500V, 20A, 80A pulsed), or the IRFP460 (500V, 0.27 Ohm, 20A and 80A pulsed).
A free energy book listing many free energy devices written by Patrick Kelly.
Dynamic dV/dt Rating, Repetitive Avalanche Rated, Isolated Central Mounting Hole, Fast Switching, Ease of Paralleling, Simple Drive Requirements.