Re: transformer fed magnifier vs. coupled coil feed/ Curiosity killed the cat

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

Original poster: "rob by way of Terry Fritz <twftesla-at-qwest-dot-net>" <rob-at-pythonemproject-dot-com>

Tesla list wrote:
> 
> Original poster: "rob by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<rob-at-pythonemproject-dot-com>
> 
> Tesla list wrote:
> >
> > Original poster: "rob by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> <rob-at-pythonemproject-dot-com>
> >
> > I finally got the time to try out a coupled coil feed to my small FET
> > driven magnifier coil.  Compared to the ferrite transformer bottom feed,
> > there doesn't seem to be much difference in the output.  I tried a few
> > variants on # primary turns.  There may be a difference in efficiency,
> > though, although I didn't explore that very much.  I was mainly looking
> > at how long the streamers were.
> >
> > My next experiment is going to be to put that big ferrite rod back in
> > the center of the coil and see if I can finally find the resonant freq.
> > Will be sort of like a cylindrical flyback :)  Late night fun!
> >
> > Rob.
> >
> > --
> > -----------------------------
> > The Numeric Python EM Project
> >
> > www.pythonemproject-dot-com
> 
> I finally got resonance with a ferrite loaded coil.  I had to use a
> 4700pf cap on my TLC555 instead of the usual 150pF.  It put out less
> voltage but much more current.  I was using a primary coil connected to
> the FET.  I think if I can reduce the primary winding, I might get a
> much higher secondary voltage.  Right now it is too highly coupled.
> Rob.
> --
> -----------------------------
> The Numeric Python EM Project
> 
> www.pythonemproject-dot-com

Well, I kept decreasing the primary turns and getting higher output, and
adding caps to resonate it, then finally, boom!
I blew out my IRFP510, UC2710 driver, the TLC555, and the 8V regulator
driving the UC2710.  Curiosity killed the cat.  I still think a small
ferrite loaded coil is a viable concept.  Luckily I had lots of spare
parts.  Next time I will use a current limiting resistor, and a variable
cap for the primary.  I'm only driving it with 30V.  Rob.

-- 
-----------------------------
The Numeric Python EM Project

www.pythonemproject-dot-com