Here are two electrostatic versions of a retro Click-Clack toy that were popular in high schools back in '70s. Version 1.0 is the super-budget model. Parts (excluding the power supply) amount to almost nothing. A description of the more expensive and upgraded 2.0 version pictured on the Intro page appears at the end of this i'ble.
I used conductive spheres to shuttle electric charges between the poles of a high voltage (HV) DC source. This shuttle assembly was made from two, foil-covered spheres joined by a non-conducting, plastic tube. The assembly was sandwiched between two stationary, dumbbell shaped electrodes. When the upper dumbbell was grounded with respect to the negatively charged lower dumbbell, the shuttle began to bounce between the HV poles with a clacking noise as charges were transferred from the lower to the upper electrode. This rocking motion completed the HV circuit.
I powered the project with an electronic air ionizer purchased at a rummage sale; but other sources of HVDC, such as a Van de Graaff generator could be used to rock this clacker. For a video clip about the project, click here: http://www.youtube.com/watch?v=eQrXRCu066c
If you choose a commercial air ionizer as the power source, use a model powered by a low voltage AC adapter. A line powered ionizer can be a serious shock hazard!!
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