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Ok, so I've been designing a High voltage Low amperage supply, so far I have 2 9V's in series with 2 momentary push buttons as the triggers. Then the 18V from the battery is stepped up by a Flyback transformer from an old CRT TV. Does a Flyback need AC or can it run on 18V DC? Also, I think I'll use a Current devider to take the current down to a non-leathal 15mA. What resistors should I use? Are there any better I deas out there? I'd love to know! Thanks.

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Somebody reply please?

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Look see around on the www.  You should never hook up AC to one of those ( or anything for that matter...)

There is a kitset around I seen for making a 'jacobs ladder' which makes a high voltage spark with very low current from a DC supply / power pack.

What you need is an oscilator to drive the coil.  Most of these circuits have in mind safety so limit the input current and voltage.  The oscilator makes a big choppy sqaure wave in one system and this is fed into the coil.

Do a google search for fly back oscilator projects etc and see what images come up...  Post links here and we can comment

TAKE CARE !

~ Andrew

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So, I'm gonna harvest the flyback from a CRT TV would ther be an oscilator in there already?

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Heres a crude circuit diagram:

MPB1 and 2 are the triggers, 18V is the 2x 9V bateries, T1 is the flyback, R1 is the current devider (What value?).

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Yep; a bit rough...  You need to 'chop' DC to get it turned into a rough waveform to get it to go though a transformer to step up the voltage.

For safety sake I suggest you lookk for project ideas like this site:
http://www.rmcybernetics.com/projects/DIY_Devices/homemade_tesla_coil.htm

or get a kitset from Jaycar etc to make a jacobs ladder
http://www.jaycar.com.au/productView.asp?ID=KC5445

Using a kitset like this is much more reliable (and I.e. Fun ) Also safer as the energy is limited and or all the warnings and safety features are there

~ Andrew

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I'm trying to do this project at no cost, that's why I'm getting the flyback from an old CRT,would it include a DC 'chopper' that I could harvest? Where could I get one if not? This is ultimatley going to be safe so the voltage is intended to be as high as possible and the current at 15mA.

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We can not support making things that will cause harm or weaponry on the HUB.  So I suggest you start calling it something else ! 

A lot of circuits can be made to self oscilate with just a single transistor but this will depend on the type of coil you have.  I circuit and diagram on the www will be the way to go here.  I looked and there are lots of diagrams.  

Otherwise you will need an oscilator e.g. a 555 oscilator and a power transistor to chop the DC up. 

~ Andrew

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Would this suffice? I found it on instructables: http://www.instructables.com/id/2n3055-flyback-transformer-driver-for-beginners/step3/Putting-the-circuit-together/

(Not my design) Of course changing the values of the resistors and transistors to suit my input voltage. Think it'll work? And if you do would It be possible to aquire the parts from you? At what cost/points?

Would a MJE3055 be a suitble replacement for the 2N3055? And leave the Resistors as they are?

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Progress: I've got the Flyback! I still need to de-solder it off of the PCB, I'll do that tomorrow in Electronics Class. The Voltage out is at max 40kV now, hope it reaches that. Somebody reply to the above message? I need answers so I know whether or not to get the parts.

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More progress: I've wound the primary and secondary coils using Enameled magnet wire salvaged from the same TV, 11 Windings for the primary, 7 for the flyback winding. All I need now is the resistors and transistor.

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Nearly there: in electronics class today I put together the driver circuit on a kiwi pach circuit board.

I got the Transistor from here and the 2 resistors from my electronics teacher.

Now I need to add power in and power out leads i'll do that next electronics class I get.

After that all I need is a couple of 9V cells.

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Ok, I'm not gonna lie, there was some trouble on the way, but NOW all I need is the 2 9Volts. :P