Re: Welders vs. Variac ballasts, was Rotaty popping, (Was Re: comm

In a message dated 4/29/00 7:05:21 PM Pacific Daylight Time, tesla-at-pupman-dot-com 

<< Hi Ed,
 OK, so the welder was infinitely variable, and had a wide inductance 
 range.  Did you ever use the welder with the .05uF cap, or only with
 the .025uF set up?  I'm thinking maybe that made the difference....
 the cap size?  I'm still having trouble seeing what the difference would
 be between a welder and a variac if they both have the same inductance
 (other than saturation issues that is).  Maybe the welder inductance
 did not go low enough?  I'm wondering if the improvement you're seeing
 is due to the larger caps, not due to the use of the variac.  Although it
 is possible that when you added the larger caps, you no longer had
 enough inductance range in the welder.  A different sized cap, requires
 a different amount of inductance.  Also, for a given total power and 
 spark length, a larger cap will not need to charge up to as high a
 voltage assuming the break rate is still the same, so this in itself
 would keep the cap voltage lower, etc.
 I think the variac has a lot of inductance for its size because the
 toroidal core shape really does a good job of containing the 
 magnetic flux.
 John Freau

I did run the coil with the original .025 ufd cap and the new variac ballast. 
 I stayed with the same cap until I solved the 60 hz primary resonance 
problem.  Once I got the problems resolved and the coil running smoothly, 
then I added the second cap in parallel.  The problems using the welder 
remain a mystery to me.

Ed Sonderman