[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
RE: Odd numbers
Hi all,
Thanks Bart :)
Obviously I have some glaring flaws in the math, but I plead "public
education."
That being said,
I'm leaning towards the higher voltages more than higher current. Okay,
really I want both, but voltage looks to be a more worthwhile increase.
Maybe I should go get that 28kv PT...$250 for it I believe. I dunno. Got
other bills too :(
I was using a simple increase in current vs voltage, because I can stack
on a few more NST's easier than I can obtain that PT. Also, working with
the "fragile" NST's, I have to be careful of letting the voltage rocket up.
Being limited to MMC's and NST's for the moment, I'm trying not to cook
anything too vital before halloween. I expected poorer performance from the
high-current approach, mostly being burned off as heat, light, & noise in
the gap. 'Gap radiation' i'd call it.
Okay, now I'm seeing a lot more of the picture. Hmm. So for voltage-ly
challenged individuals whom can't obtain 15/30/60/whatever NST's, current is
our only answer once we hit our voltage limit. I have only 1 15/30, but
more 12/30's than I have 120v current. Er, had, a few died.
So now it's a question of making it more efficient. Enter John Freau.
More secondary turns, more primary turns, better gap and higher primary
voltage. Now, that 28kv PT will kick out ~40kv peak-peak. Ouch. That's
commercial-cap land. A whole 'nuther post :) Hmmm...that PT is lookin
better and better, despite the cost of the commercial cap it'll require. At
least it's capacitance needs will be low, as it's 28kv-at-1700va (~60ma?). I
think it'll take 2x current for a bit, but it's only 120v input! Lots 'o
amperage needed...darn...I'll research it a bit more.
My curiosity sated for now on this matter :) Thanks
Sundog
-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Thursday, September 14, 2000 7:34 AM
To: tesla-at-pupman-dot-com
Subject: Re: Odd numbers
Original poster: "Barton B. Anderson" <tesla123-at-pacbell-dot-net>
Hi Sundog,
Tesla list wrote:
>
> Original poster: "sundog" <sundog-at-timeship-dot-net>
>
> Hi All!,
>
> I had myself an idea (Quick! Run and hide!), and plugged same #'s into
> Wintesla.
>
> 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?
Right, (V^2 should be Vp^2).
>
The 12/30 will have a stronger magentic field assuming the solenoid doesn't
totally load it down. It's the voltage over the solenoid impedance that
determines the magnetizing current, not the current rating of the tranny's.
The
current rating identifies only the tranny watts. The solenoid itself will
determine actual watts - the load.
>
> 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)
Both are worthwhile. In TC setups, the cap size and gap distance determines
the
bang and cap voltage. Have you ever wondered how a gap distance that is
suppose
to arc at 40KV can actually arc across that gap with a tranny spitting out
only
12,000V? Because the cap voltage climbed until it arc'd. The 40KV potential
and
the capacitance will instantly let you know the bang size by 1/2C*Vp^2 (so
will
your ears) and vise-versa - the gap distance will identify the cap voltage
if
you were sure about the arc potential required to arc across the gap being
used. To do this right, you would need to set up a test ficture with known
ROC's and sizes for arc distance to voltage, then place in your gap and test
at
that voltage (most likely, the distance would be increased a bit to match
since
typical spark gap tables use sphere's and we typically use something else
like
copper piping or whatever). Jim Lux is real good with stuff.