Re: My PT is loud!

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

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

Hi Drew.  When my tranny's bite the dust they end up giving out a real
loud, vibrating 60 cycle hum. The shorted tranny wants to "walk"
(vibrate) across the surface it is placed upon.  Sometimes a shorted cap
will also do this also, as will most any direct short across your
tranny's secondary.  But usually the loud hum is from a shorted secondary
winding on the tranny itself, and the secondary windings got awful hot
really quick.   Hopefully your tranny is O.K.   AL

On Wed, 21 Feb 2001 11:38:57 -0700 "Tesla list" <tesla-at-pupman-dot-com>
writes:
> Original poster: "Metlicka Marc by way of Terry Fritz 
> <twftesla-at-uswest-dot-net>" <mystuffs-at-orwell-dot-net>
> 
> drew,
> first off i would say your capacitor plates are shorting across. my
> plate caps would hum when they shorted also. are you using any oil 
> for
> the cap?
> also, do you realize that by placing 300v into your pt your pushing 
> it
> to 14847v p-p? that's 3.5 times it's rated input threshold, with any
> kick from the tesla coil the insulation stress will be great.
> it seems to me that you will have fried your new transformer before 
> you
> even get a chance to display it, though you got this one for free, 
> pt's
> are hard to come by.
> marc m.
> 
> Tesla list wrote:
> > 
> > Original poster: "Drew Murray by way of Terry Fritz
> <twftesla-at-uswest-dot-net>" <drewallmighty-at-hotmail-dot-com>
> > 
> > Hello,
> > I am almost finished my coil. I took everyones advice and redid my 
> primary.
> > I don't want to risk cooking my secondary with the Vertical helix 
> primary. I
> > have finished winding my 8" x 32" pvc secondary. I gave the pipe a 
> thin coat
> > of poly before i started winding. I didn't have much left in the 
> can as i
> > used it for my last coil. I have all of the current limiting and 
> power
> > control equipment set up for the PT and i have been having fun 
> watching the
> > heat waves totally distort the wall behind it from my jacobs 
> ladder. It can
> > climb untill the flame is something like 5" long. Anyway,
> > I have been experimenting with around 323 1 gallon zip lock bags 
> with the
> > zip locks cut off, and some foil plates, trying to make a 
> capacitor. I
> > noticed that if i got the capacitance way too high, and i turned 
> up the
> > variac to the pt, no sparks would jump the 1/2" saftey gap on the 
> pt. It
> > worked with a 16 wine bottle salt water cap! When i turned it up 
> to around
> > 60% A really loud buzzing/humming noise would come from either the 
> PT or the
> > capacitor, which i have watched vibrate voilently before. It would 
> stay loud
> > until i turned everything off. What the heck is happening here? It 
> is a
> > 120:4200  -at- 1000va, but i have been feeding 300v into it from a 
> step up
> > transformer, so i can get 10500v out of it. 4200 just wasn't 
> enough. and
> > could somebody show me how to get the right size capacitor with my 
> zip lock
> > bags and aluminum plates? I really need to know this.
> >                                                        The Young 
> coiler
> >                                                         Drew 
> Murray
> > 
>
_