Re: SSTC2 - Four Foot Arcs . . . well until . . .

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

Original poster: "K. C. Herrick by way of Terry Fritz <twftesla-at-qwest-dot-net>" <kchdlh-at-juno-dot-com>

Welcome to the club, Dan.  Check Future/Active for replacements: they're
generally a lot cheaper than DigiKey.  I've bought hundreds of MOSFETs
from them, most all gone bye-bye now & often in the same way.  At least
mine were "only" $3 each...

KCH

On Tue, 06 Aug 2002 12:39:00 -0600 "Tesla list" <tesla-at-pupman-dot-com>
writes:
> Original poster: "Mccauley, Daniel H by way of Terry Fritz 
> <twftesla-at-qwest-dot-net>" <daniel.h.mccauley-at-lmco-dot-com>
> 
> 
> 
> I had time to fiddle with my SSTC2 (as seen on 
> www.spacecatlighting-dot-com)
> some more while waiting for additional components for my 
> conventional tesla
> coil.
> 
> I used a 240VAC, 40A variac to power my 5kVA 120VAC to 480VAC 
> step-up
> transformer to provide power to my full-bridge SSTC circuit.  
> 
> Today was the first day I would bring my coil up to full design 
> voltage
> (480VAC) and it was spectacular.  At 480VAC I was getting wickedly 
> thick
> (and thunderous low frequency loud) arcs over four feet in length 
> shooting
> upwards (through my discharge point) on my toroid up to the pipes in 
> my
> basement ceiling.  I've seen conventional coils run at similar arc 
> lengths,
> but nothing as thick and sinister as these things were.  
> 
> 20 seconds pass . . .
> 
> Hmmm . . . whats that smell . . . maybe i should be paying more 
> attention to
> it.  Yeah, but this is too cool.  Let me grab my camera in the other 
> room.
> 
> . . . walking the 10 feet i need to other room to get my camera . . 
> .  BANG,
> BANG, BANG,    SCHKLLLAAMMMMMAMMMMM  ! ! ! ! !
> 
> "OH F#$-at-!!!!!"  Fire on the carpet, fire on the carpet . . .
> 
> Well, too make stories short, all four 1000V FETS (IXFN24N100 type) 
> blew up
> to smithereens.  No, these didn't just crack and blow some smoke, 
> they
> actually blew up and some of the schrapnel had landed on a nearby 
> throw rug
> and set it on fire . . .
> 
> Darn, those things were $70.00 each ! ! ! !  
> 
> Well, it was spectacular while it lasted . . .
> 
> Dan
> 
> 
> 
>