Re: purpose of a variac?

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Mike" <mike.marcum@xxxxxxxxxxxx>

That method works best with rsg's. On electrode presentation the gap 
fires at just a few kv (maybe a bit less if you wanna test your luck 
on avoiding electrode crashes). With static gaps you have to lower 
the width of the gap as well when lowering voltage.

Mike
----- Original Message ----- From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Sunday, January 22, 2006 9:19 PM
Subject: purpose of a variac?


> Original poster: "Qndre Qndre" <qndre_encrypt@xxxxxxxxxxx>
>
> Hey coilers,
>
> I've read several documents on the internet which claim that the 
> power throughput of a TC can be adjusted using a variable 
> transformer to power the supply transformer of the coil. I don't see 
> how this could be done under regular circumstances. If the input 
> voltage of the supply transformer is reduced, it's output voltage 
> reduces as well. The voltage across the capacitors can never exceed 
> the supply voltage (unless you use resonant charging which may 
> destroy the secondary winding of your supply transformer). Since the 
> spark gap in the tank circuit is best to be tuned just to fire at 
> the absolute voltage peak for optimized performance it will never 
> fire with reduced input voltage to the primary circuit.
>
> Regards, Q.