vandergraph generator

I doubt it. Its best to refine your generator. Collector site at the ball should be sharp and clean. Clean rollers and belt. Keep the outside of the ball clean. Use in dry air. Increase the speed a little if you can. If you can get a chance take your son to the Boston Science Museum to see the real one. It is quite a treat to see their demo. I never get tired of it.

Tom

You mean Van de Graaff Generator named after it's inventor Robert J. Van de Graaff. In a Van de Graaff generator the charge will build in the metal ball at the top raising the voltage until the leakage currents, corona, and other current paths equal the amount of charge being re-supplied by the belt. If you supply extra current from a high voltage source such as you mention, the voltage attained will be become higher because the charging current is higher. A well designed, and insulated generator, operating in dry air may attain voltage high enough to spark from the ball all the way to ground. Very impressive. The added charge should be "sprayed" on the belt from the lower brush in the unit's base. Of course, it must be insulated from the frame.

Reminds me that I haven't seen that show in years. Have to get up there again.

Hell yes! That's how it is done on the big machines.

Thanks guys Then I take it that an Ion generator will make a difference do you think this one will do or should I look for something bigger

m/QK57

Thanks guys Then I take it that an Ion generator will make a difference do you think this one will do or should I look for something bigger

I don't think an ion generator will make enough difference for the money.

Why not use an old crt monitor or tv as primary voltage source?

Sure that would work. The current output of the multiplier can be increased by increasing the capacity of the caps - the diodes are usually just loafing along at a few micro amps.

That ion generator is mains operated and only isolated from the power mains by the caps - so be safe.

The voltage will increase but is still limited by the size and shape of the collector. What increases more dramatically is the ability to charge up again after a discharge (or the current output) and it will compensate for some of the losses to corona and humidity.

The current output of the ion generator can be predicted based on the cap size - probably from the capacitive reactance of the (series) caps

- but there are some sites with information on that if you search.

check out:

The excitation system for the machine can be built in many ways. There is the original, and best, using an electronic excitator to spray charge in the belt, and many other possibilities, that can be identified with the charging systems of the classic friction and influence machines. This picture shows some of the possibilities.

PS bear in mind - the ion generator should have the same polarity as the terminal it will be charging . . .

A web search with the correct spelling may help " Van De Graaf".

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