Magnetic Quench Spark Gap (Capacitor Discharge)

[masonmilburn]

what did you use to make this send me drawing

[SpecklePattern]

So is it discharging more frequently due to Lorentz force or why it sounds that the spark frequency gets higher with the strong magnet.

[johnb003]

@SpecklePattern It only takes me 1 year to reply... sometimes... I think the sound is higher/louder because the discharge is more abrupt. The energy from the capacitor discharge is not allowed to be a "soft" discharge, it has to happen more suddenly because the lorentz force is pushing on the arc as current flows. This probably causes the cap to charge a little higher before it can discharge again, and so, more energy louder sound.

[IST814]

verry nice!

ist

[cheaphardwarez]

If only ppl would learn to use these with tesla coils! It makes a BIG difference when the coild is pulsed DC and NOT AC

[DarkShroom]

@cheaphardwarez forgive my ignorance but isn't pulse dc the electircal equivilent of as as it just to full potential then drops back to 0? is it better for sparks perhaps because you're always pushing the electrons one way?

[johnb003]

@DarkShroom instead of a nice smooth wave signal you'd have a periodic spike. Cap discharge spark gaps are used in tesla coils often to perturb the proverbial string that is the inductor / capacitor resonant circuit. By using this magnetic quench approach the inpulse duration is shorter and thus a higher instantaneous power is produced.

[DarkShroom]

@cheaphardwarez sorry i meant equvilent of ac

[sciencekid17]

the capacitor lookes like a c1 class 200v 1uf film capacitor though

[gotoluc]

Nice work johnb003,

a neo magnet can do what a 555 and transistor does for switching.

Have a look at my video response

Thanks for sharing.

Luc

[johnb003]

You're right you could do it, cool video!, but I don't think it would be better than a 555. I think it's the same as using a relay, and then you still have a low current limit and need to use a transistor or power mosfet, and the relay has mechanical contact sparking which, if nothing else, will wear it down faster.

[TerboBlitz]

Interesting. Is the flyback output unrectified (AC)? Also, what is the cap value (voltage & nF)?

[johnb003]

The flyback internally is rectified. There are diodes on each layer of the secondary. The voltage difference between each layer isn't that much so this means they can use a series of less expensive diodes.

The reason it's rectified is because the purpose of the flyback is to charge the crt, which is a big laden jar.

If I'm reading the code on the cap correctly (it says 0150), then it's 0.104 nF (104 pF).