Posted: Mon Dec 14, 2009 4:59 pm
Ile just reinforce what everyone else is saying 
SCR's, as said, are only needed when repeatability, durability, and control are needed. Don't think solid state is superior, solid state has its disadvantages like ESR.
I am planning a triggered spark gap for my 12,000 joule cap bank, for both the railgun and a future ETG.
For 200 joules, look for a large relay or contactor, or a knife switch. You can also do spring loaded plates. If you want a handheld, I would do a mechanical solution, a copper block is attached to a lever attached to the trigger, which contacts a stationary copper piece inside. A spring will help release it, and provide tension to the gun doesn't trigger when you tilt it.
Consider a small magnet in the beginning of the barrel, so the projectile doesn't fall out.
knife switch:
http://www.smithae.com/wirthco_knife_switch.jpg
Start with the boost converter, and we can help from there.
SCR's, as said, are only needed when repeatability, durability, and control are needed. Don't think solid state is superior, solid state has its disadvantages like ESR.
I am planning a triggered spark gap for my 12,000 joule cap bank, for both the railgun and a future ETG.
For 200 joules, look for a large relay or contactor, or a knife switch. You can also do spring loaded plates. If you want a handheld, I would do a mechanical solution, a copper block is attached to a lever attached to the trigger, which contacts a stationary copper piece inside. A spring will help release it, and provide tension to the gun doesn't trigger when you tilt it.
Consider a small magnet in the beginning of the barrel, so the projectile doesn't fall out.
knife switch:
http://www.smithae.com/wirthco_knife_switch.jpg
Start with the boost converter, and we can help from there.