Re: Just wound 1st 2ndary, need help sizing primary, other Q's...

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>" <Tesla729-at-cs-dot-com>

In a message dated 4/2/01 10:53:54 PM Central Daylight Time, tesla-at-pupman-dot-com 
writes: 


>
> "Bill Vanyo by way of Terry Fritz <twftesla-at-uswest-dot-net>" <vanyo-at-echoes-dot-net> 
>
> I just finished winding the secondary for what will be my first coil, 
> and I must say, it is a thing of Beauty.  It's on the winding gizmo now, 
> with it's third coat of polyurethane drying. 



Hi Bill, 

Congratulations! It's good to hear that you have successfully 
constructed a "good looking" secondary coil. 

<I have a couple of power supplies to work with: A 15/30 NST, a 15/60 NST 
<and this transformer from an X-ray power supply, which I got off eBay: 

<http://cgi.ebay-dot-com/aw-cgi/eBayISAPI.dll?ViewItem&item=1223896601 

<the exact specs of which I'm uncertain, but will be using a variac to 
<control it. 

I'm afraid the x-ray transformer isn't very suitable for a Tesla power 
supply transformer although it does make for one heckuva HV source 
( ~ 100 kVAC - with significant current). It's output voltage is just too 
high for a practical Tesla power supply and if you gate it back to the 
typical 10 to 20 kV Tesla range with a variac, then the output current 
will probably be too small to properly charge the primary capacitor 
for the sized coil that you're building. 

Also, unlike NSTs or OBITs, that x-ray transformer ain't current limited. 
That means that you would have to employ some means of external 
ballasting to be able to use it in a Tesla configuration or it would short 
out and probably blow a fuse/ trip out a breaker. And this x-ray transfor- 
mer is VERY LETHAL if you make a careless mistake. 

<I know it may seem like I'm starting out big for a first coil, but I'm 
<hoping to build something that will leave me satisfied enough that I 
<won't want to build another one soon - it's a lot of work. 

I'd say NSTs are the best bet for a beginner coil. Most coilers go thru 
the learning curve before attempting a really large coil. All Tesla coils 
are potentially dangerous (no pun intended), but the really large ones 
are positively lethal for a careless mistake. An NST or OBIT transform- 
er can cause a very painful and nasty electric shock, but a PT, plate 
transformer, pole pig, x-ray transformer, ect. can KILL you in a very 
short order! 

Hope this Helps, 
David Rieben