Thread: Bedini SG
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Old 12-31-2007, 10:21 PM
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ren ren is offline
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Join Date: Oct 2007
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Nice job on the tri Sep For small bearings guys check out hobby shops that have RC planes/cars, they usually stack a heap of different sizes for wheels etc and they are all small and high speed. I got mine from a vcr head. They already have a shaft and housing for them too.

In regards to magnets here is my opinion. The wheel is basically a timing device no? You can harness it for mechanical output but it basically is there to switch the coil on and off. You want the switch to be as fast as possible, i.e. on suddenly and off suddenly. With a more powerful magnet the on time would be longer as its magnetic field passes the coil as opposed to a thin weaker magnet. Obviously the base of your transistor needs a minimum amount of current/voltage to trigger it into action, so there is a bare minimum. I have used a ferrite magnet 10mm cubed to trigger a coil and it worked quite well. I cant compare results as the coil was tiny, but charging rate seemed satisfactory.

This could also be the reasoning behind adjustments in the air gap giving different results in charging. Further away and the magnetic flux pattern of the passing magnet is only just touching the coil and only just triggering it too.

Just my musings, someone come and explain it otherwise if its wrong
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