Doesn't work Don't ask me how I know.
You'd need something to attract the spark in that direction.
I'm not aware of TV or movie prop techs building EMP devices to take out an entire city block...
I gave you an opportunity to deny it and you admitted you DID want to know so that's where we're at.
No matter how you slice the cake, if you ask how to do something that can cause chaos or harm, there will be objections.
Read this about vacuum tubeshttp://www.vacuumtubes.net/How_Vacuum_Tubes_Work.htm
(The Electronic flash is about 350V, and nearly-lethal energy. Short the cap (carefully) and you get the first type of sparks. The flash itself is more the second type (but specialized, cause ionized Xenon and stuff.)) Sparks are actually rather complicated things...
We all know a French baguette would just surrender
The person I was with when I did that spark measured 720v before we discharged it. Me being so new to all of
There's also a point that states you can manufacture explosives without any license in a certain low quantity without storing them if the point is research or experimentation,
Sounds like you are in the UK.The 100 gram rule.Black powder is a special case , if you make it you have aquired it and an aquire licence is required.The law was recently changed so that a BP licence can be had as pyrotechnic use is now a valid reason to apply for one. Other restrictions apply.Best place to look is the UKPS who were instrumental in having the law changed.