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    Hello. I've noticed that for creating "sparks" with an transformer I need an oscillator. I want to know if I can use arduino for this. I'm afraid of breaking it because of the high voltage that it would generate.

Here's my schematics: enter image description here

    I programmed arduino to pulsate the current on pin D11. The current will open the transistor and the transistor will close the transformer's circuit and that will produce a voltage which will be stored in a capacitor.
   I've inserted a diode because I am afraid that the arduino will "burn". Is this safe(for arduino)? Are the schematics correct? Or should I quit? (Sorry for my mistakes. This is not my original language)

EDIT
    The transistor is NPN. And the transformer's current source is the 10 V Battery..
    I don't want to use an "classic" oscillator because for me is hard to make one(from transistors) and I'm just a child so I can't buy anything from internet(for example a 555 timer).I got the arduino and the rest of the pieces from my uncle.

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  • \$\begingroup\$ Why use an arduino just for an oscillator? Why not use an oscillator circuit? Depending on your frequency, a basic relaxation oscillator should do the trick. \$\endgroup\$ – Jarrod Christman Aug 22 '15 at 15:44
  • \$\begingroup\$ My concern would be that the transistor and transformer are too small, and the 9V will not be able to supply enough current for it to operate properly. You haven't mentioned the transistor or type of transformer you're planning to use. Plus, what you have shown are not schematics. Personally it drives me crazy when people use Fritzing or whatever software that is. It makes it very difficult to see what's actually happening \$\endgroup\$ – DerStrom8 Aug 22 '15 at 15:44
  • \$\begingroup\$ @Jarrod Agreed, but for experimentation I too like using a mcu. Very versatile, straightforward to change / sweep frequency or duty cycle. Even easy to record, say, output voltage as a function of frequency in one sweep. \$\endgroup\$ – Nicolas D Aug 22 '15 at 16:02
  • \$\begingroup\$ I wouldn't combine a spark-generator and a microcontroller in one circuit. Better take basic 555 oscillator and add a power darlington (with abse diode) or mosfet. Don't forget to protect the transistor, for instance with a zener diode (the classic diode over the primary coil absorbs all the spark energy). \$\endgroup\$ – Wouter van Ooijen Aug 22 '15 at 16:12
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    \$\begingroup\$ Choose a safer project. You can easily throw your heart into fibrillation with such a thing. \$\endgroup\$ – Jarrod Christman Aug 22 '15 at 18:10
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I suppose in your "schematics" the npn base is the middle pin? In that case you'll indeed fry the arduino (or transistor, or diode, or...) because there is nothing limiting the current.From arduino pin to ground there is the equivalent of two forward biased diodes, which at reasonnable current levels would drop about 1.5v. Forcing 3.3 or 5v across that means unacceptably high current.

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  • \$\begingroup\$ Can you explain more ? Which pin? The Ground pin or pin D11? And can you explain what you meant with "there is the equivalent of two forward biased diodes" (I know what "forward biased diodes" means..)? \$\endgroup\$ – Emil Reznicencu Aug 22 '15 at 16:07
  • \$\begingroup\$ If you don't know what that means, you shouldn't be working on this project. I suggest building an LED flasher if you want a project. Or a tone generator. Something safe, anyway. \$\endgroup\$ – DerStrom8 Aug 23 '15 at 1:07
  • \$\begingroup\$ Though, note that even in an LED flasher, you'll need to limit the current draw. LED's, transisters...etc all behave like diodes and their current draw increases exponentially. Also, @Emil, we're not trying to discourage you from electronics. It's just that your chosen project is quite a bit more dangerous than you seem to realize. \$\endgroup\$ – Jarrod Christman Aug 27 '15 at 12:14

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