Re: Toroids

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx>

Hi Dave,

Your thinking of a single sphere topload. Were talking about 
something altogether different (Terry's Piranha Coil topload). The 
topload is made from a series of sphere's. They are expandable in the 
horizontal direction by position of the supporting rods. Take a look.

http://drsstc.com/~piranha/ <http://drsstc.com/%7Epiranha/>

Take care,
Bart

Tesla list wrote:

> Original poster: "Dave" <dgoodfellow@xxxxxxxxxxxxxx>
>
> How do you expand a ball? I find that toroids do better at 
> controlling corona at the top turns of the secondary, where balls 
> need to be placed as low as possible, at the top of the secondary. A 
> coil would look great with an insulator between the secondary and 
> the ball, but the corona becomes unmanagable.
> By the way, since Waterscapes stopped selling gazing balls at the 
> nice price, I have found the best overall price and service from Amazon.com
> Best price for an 8" is from artywoods on ebay. Don't look up 8" 
> though, search stainless gazing, and you will see his 7.65" gazing 
> ball for about $18.00
>
> Cheers, Dave Goodfellow
>
>
> ----- Original Message ----- From: "Tesla list" <tesla@xxxxxxxxxx>
> To: <tesla@xxxxxxxxxx>
> Sent: Friday, March 02, 2007 12:52 AM
> Subject: Re: Toroids
>
>
> > Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx>
> >
> > Hi Terry,
> >
> > The balls have the same advantages over toroids even with a classic 
> > coil. The toroid can be raised and lowered, but not expanded. The 
> > balls have "that" extra dimensional option. That in itself makes it 
> > a superior topload (me thinks).
> >
> > I will begin collecting these sphere's for toploads for my classic 
> > coils. You've already figured out a nice mounting technique, so 
> > once again, you did all the work and all we have to do is follow in 
> > your footsteps!
> >
> > Thanks for always being "cutting edge". I know there was someone 
> > else who had also did the same (he's cutting edge too!). It's not a 
> > knew idea as most coilers have contemplated various topload 
> > configurations (sphere configurations are always part of that 
> > thought process). The difference is "you did it"! And it "is cool"!
> >
> > I can even imagine a sphere topload like this on a super huge coil. 
> > What a nice way to cut cost and enhance topload adjustment.
> >
> > Take care,
> > Bart
> >
> > Tesla list wrote:
> >
> > > Original poster: Terrell Fritz <terrellfone@xxxxxxxxxxxxxxxxxxxxxxx>
> > >
> > > Hi Jim,
> > >
> > > PIRANHA-II can make "very good" use of an adjustable top 
> > > load!  The primary is pretty well "fixed" hiding in its "bunker" 
> > > and not meant to be "tuned in" ever again at that point (just like 
> > > Cheney >:O))...
> > >
> > > http://drsstc.com/~piranha/PrettyPictures/Construction/PIRANHA-Const-012.JPG 
> > >
> > >
> > > http://drsstc.com/~piranha/PrettyPictures/Construction/PIRANHA-total-02.JPG
> > >
> > > The primary coil was chopped down step by step until the right 
> > > point was found:
> > >
> > > http://drsstc.com/~piranha/PrettyPictures/Construction/PIRANHA-Const-004.JPG 
> > >
> > >
> > > http://drsstc.com/~piranha/PrettyPictures/BallTerminal/Tuning.JPG
> > >
> > > The balls just slide in and out on the brass tubing from the hobby shop:
> > >
> > > http://drsstc.com/~piranha/PrettyPictures/BallTerminal/TerminalTuning.JPG
> > >
> > > This varies the coil's secondary capacitance from 28 to 34 pF.
> > >
> > > http://drsstc.com/~piranha/PrettyPictures/BallTerminal/TerminalTuning.gif
> > >
> > > Combined with the 73.63mH secondary, I can tune from 100.6 to 
> > > 110.8 kHz. So if you can get the coil's tuning pretty close in the 
> > > first place, no need for primary tap adjustments.  I do hold the 
> > > rods in place with a bit of tape since the balls will slide right 
> > > off if tipped otherwise.
> > >
> > > Adjustment is useful in say going from an enclosed room to outside...
> > > Instead of moving the primary tap around for the best arcs, you 
> > > just slide the terminal ball in and out for the best arcs...
> > >
> > > The ball terminal works pretty good:
> > >
> > > http://hot-streamer.com/temp/DaveBaehr/b01_2858.jpg
> > >
> > > They really are much like a conventional torroid:
> > >
> > > http://drsstc.com/~piranha/PrettyPictures/BallTerminal/newcoil-00.jpg
> > >
> > > http://drsstc.com/~piranha/PrettyPictures/BallTerminal/newcoil-01.jpg
> > >
> > > I really don't think I will ever plane on using anything "else" 
> > > now...  In order to save lab space, I think I will just "crush and 
> > > discard" my old big dryer duct toroids since this new terminal is 
> > > pretty universally useful for all my coils now.  I guess I 
> > > consider dryer duct and aluminum "real" toroids "obsolete" and far 
> > > too expensive now...
> > >
> > > I do note that at lower indoor power levels, I have to use a 
> > > breakout point or it just sits there and glows...
> > >
> > > http://drsstc.com/~piranha/PrettyPictures/BallTerminal/PIRANHA-DragonsGlowing.JPG 
> > >
> > >
> > > The dragons and all exposed metal ,like the handles, are fully RF 
> > > grounded...  Sort of a "hidden" strike ring...
> > >
> > > Cheers,
> > >
> > >         Terry
> > >
> > >
> > > At 06:09 PM 2/28/2007, you wrote:
> > >
> > > > Original poster: "Jim Mora" <jmora@xxxxxxxxxxx>
> > > >
> > > > Hi Terry, et al,
> > > >
> > > > There's no rain on the parade. The PIRANHA II is a work of art as well as a
> > > > technological innovation!
> > > >
> > > > Perhaps a better route would be to use dyer duck to bring the coil up, and
> > > > as time allows build the adjustable ball top load. Do you feel it needs to
> > > > be adjustable at this point? I am looking at using 6" OD Lexan or
> > > > Polystyrene. Is there any value to wind to 24" and add a little more
> > > > inductance to the primary?
> > >
> > >
> > > ........