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High voltage supply questions!

  1. Aug 7, 2010 #1
    High voltage supply questions! :)

    Ok, well a few friends of mine have come together to build a fuser and an electron accelerator.
    I have obtained an NST at 20ma 6 kv DC , but would like to build a crockcroft walton voltage multiplier for the accelerator. My question is, will this setup run off a constant DC ? Or must it be a pulsed DC or an AC current. My voltage goal is +/- 100kv at no load. What parts and what method would be needed to construct this. (as in where to find the HV diodes, and what type of capacitor) I'm aware i could run the CW multiplier off of the house current, but the amperage is too much for the wire.

    Also for the CW multiplier, could home made laden jars be used? And i've seen some built with a rectifier, why is this if it is supposed to convert ac to a higher dc voltage on its own.

    The other power supply witch is more ideal for the fuser, needs an ability to take my 6kv NST DC, and up it to at least 25 kv 20ma DC at a constant rate. How would i do this? Capacitors in series are a daunting task. Would it be much easier to build a ready made power supply? Thanks to all!

  2. jcsd
  3. Aug 8, 2010 #2


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    Re: High voltage supply questions! :)

    You could consider getting a Van Der Graaf generator. These generate 300000 volts on a good day and at a few mA. Education supply companies carry these and they are not expensive.

    Another easy source of high voltage is the EHT supply in analog TVs. This would be about 35000 volts. With the introduction of digital TV and the cessation of analog broadcasts in some countries, analog TVs should be available pretty easily.

    This supply and others in a color TV set are dangerous, of course, and you may need to get advice on using them safely.

    Do you have an evacuated chamber to accelerate these electrons in, or are you planning to do it in air?
  4. Aug 8, 2010 #3


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    Re: High voltage supply questions! :)

    If you don't know and can't guarantee to implement all the safety measures needed for operating with very high voltages then the VDG Generator is by far the safer option. It can only give you an annoying little jolt. A TV EHT supply could kill you.

    The diodes for a high voltage Cocky Wally could be hard to find and expensive. Nearest thing could be the 'stick' diodes in TV CRTs.
  5. Aug 8, 2010 #4
    Re: High voltage supply questions! :)

    Well the original idea was to create an accelerator that we could charge up capacitors using the CW or VDG, and then release this energy into the magnets. And yes these are being accelerated in a vacuum.
  6. Aug 9, 2010 #5


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    Re: High voltage supply questions! :)

    I'm not comfortable with this discussion of HV generation by amateurs (the OP) -- it falls under the "dangerous activities" portion of the PF rules. Sorry, thread closed.
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