will not only compress the flux of the magnetic field of the coil 10 but will also reduce the inductance of the coil 10 if all of the mechanical energy acting on the core 20 is converted into electrical energy at the peak of such current pulse the core 20 will tend to be drawn back into the coil 10 resulting in a decrease in the current pulse as the core 20 reenters the coil 10 the inertia of the core 20 would tend to produce a negative pulse as the core 20 moves in the direction opposite that indicated by the arrow 22 within the coil 10 however the diode 14 will prevent any negative current flow through the load and coil and the open switch 18 will prevent any current flow through the battery 16 thus although the residual magnetism of the core 20 and its inertial motion in a direction opposite to the arrow 22 may generate a voltage across the diode 14 no energy exchange can take place the device shown schematically in fig1 would be complicated and inconvenient to construct with sufficient power output to be of interest however if mechanically configured as shown in fig2 a 2c a substantial power output can conveniently be obtained in fig2 a 2c the electronic circuitry would be functionally the same as that shown in fig1 and thus the same reference numerals have been used for equivalent elements however in fig2 a 2c the inductive coil 10 comprises a plurality of elongated parallel strands extending perpendicularly to the plane of the paper as indicated in cross section by the circles 10a 10d of fig2 a as described herein.