This Pixii Generator was commissioned to me by a Finnish museum and delivered in 2013.
Hippolyte Pixii (1808–1835) built in 1832 this early form of alternating current electrical generator, based on the principle of magnetic induction discovered by Michael Faraday. Pixii's device had a spinning magnet, operated by a hand crank, and a stationary dual solenoid, wound around a U-shaped soft-iron core. A voltage pulse was generated each time a pole passed under the solenoid. The pulse polarity was alternating as was the magnet pole polarization being in proximity of the solenoid core ends.
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My replica uses an old hand crank from a butter churn. This was the part most difficult to find. The magnets (3 bars) are Alnico, kept together by the brass rotor.
The two solenoids are hand-wound and mounted on an U-shaped soft-iron core. The core had to be made by a blacksmith, as I couldn't find anything ready and big enough.
The hand crank is mounted on a wooden base which slides between two guides and locks into place by four butterfly nuts.
The coils account for about 100 ohms each, making a series of 200 ohms. The voltage generated is about +/- 15 volts but the pulses are pretty sharp. The power generated is not sufficient to light an incandescent lamp but LEDs ligth really easily.
I put two white big LEDs in antiparallel, ligthing up in turn to demonstrate the alternate polarity of the generated voltage.
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