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I had myself an idea (Quick! Run and hide!), and plugged same #'s into
I was looking at the J per bang figure, and since the more J you push, the
bigger the bang. J=.5*C*V^2 Right? Good. That formula itself tells me
that if you maintain the same current (30mA in the case of my example
NST's), the higher voltage units have a better watts/joule 'rating'. IE, the
15/30 charges it's reso cap to ~4.9J (did I do that right? sounds
reasonable, but it it *iss* wrong, it's consistantly wrong).
The same size bang, for a 4kv tranny takes ~115mA (aroung 450 watts) to do
the same thing, as it's charging a 76nf cap. There's the basis. Now,
let's say I want a bigger bang, say, 1J bigger. I'll just increase the
The 15kv'er will see less of an increase, and the 4kv will see a fairly
chunky increase just to meet the same J per bang. But each is still ~ the
For TC's, it's been said that a higher primary voltage is better. i'm
guessing it's because a 5J bang at 4KV will sink a lot of current, but a 5J
bang at 15kv will have less current (I see the correlation of
voltage&capacitance of the tank cap there), for the same size bang. Less
current=less heat=less losses in the gap.
Okay, it's beginning to click. Now, when the gap fires, you get a healthy
dose of voltage/current into the primary. What makes a stronger magnetic
field? A higher voltage or current, or is it just a combination of both (IE,
is a 12kv30ma energizing a selenoid of wire just as strong as a 100v/3.6A?)
Both are 360 watts.
Okay, if it's the voltage, I can see a 28kv1.5kva PT being worthwhile. If
it's the current, I can see MOT's or a 7.2kv20-50kva PT being a solution.
On either end of the examples, quenching is a problem. The 28kv system can
ignite a long arc just by it's potential. The 7.2kv'er will try to powerarc
just by sheer current (several hundred MA at least)
A side-question: The low voltage/high current approach would need a cap
with a good DT/VT, as it's got a *lot* of juice to move very quickly,
whereas the HV caps (smaller in capacitance by far), could be a bit "slower"
i guess. ?
Soo, it all boils down to : more intense magnetic field by current or
voltage (if the total wattage is the same)?
Hmm..re-read it all, and It all looks to boil down to the total input
wattage. Only real variable I can see is the V & I. I'll be researching
this on my own, but freely welcome comments :)
now my head hurts...