Hey, I'm building a small hydrogen-powered rocket for a project.
So far, I've been using one of those push-button piezo sparkers. I'd like to switch to an electronic sparker so I can fire it using a transistor as a switch.
Would Marx generators be the best way to go? They don't seem very reliable. All I need is a small spark, maybe a millimeter long.
No need for diode multipliers, a single inductor driven from an IGBT would probably do, or
a modified flash circuit from a cheap camera? What is the voltage needed for the spark gap?
Not much really, I just need a spark. The ignition chamber is maybe 1mL, and the hydrogen is in the right ratio with oxygen, so just about anything should work
An interesting fact is that some metals suck oxygen from the surrounding air when red hot,
and thus don't reliably ignite explosive mixtures - the metal burns in preference. I noticed this
with steel wool which will burn in an air-butane mix without setting it off!
Vaporizing wire will generally work though!
Spark gaps are reusable, which is much more convenient.
What about using one of those piezo-electric igniters, like you see on push-button lighters, and for bar-b-ques? Those are fairly easy to get, and fairly low cost (cheap to free if you find an old lighter somewhere).
Every spark plug in every car has a small induction coil above it. It is fed 12 v. D.C., and when the primary circuit is interrupted, they generate a robust spark in the engine cylinder, even under high pressure. This used to be done with a single induction coil, and they can still be bought. Thier whole purpose in life is to make a really high potentail across the secondary when the current flow across the primary is broken. I used one in an electric fence. Raccoons didn't approve of it.
Someone asked me to elaborate on my rocket. It really won't take much.
I'm using electrolysis to separate about 1-2mL of water. In my current design, I have the sparking wires right next to the electrodes. The entire setup is enclosed until ignition, separated from air by around 1mL or water.
It's not very large, but it shoots very well.
And to elaborate on the spark gap, its about 0.8mm between two copper leads in a mixture of H2 and O2 gases