Re: Magnifier first light

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

Original poster: "Terry Fritz" <teslalist-at-qwest-dot-net>

Hi Antonio,

At 09:23 PM 4/24/2003 -0300, you wrote:
>Tesla list wrote:
> >
> > Original poster: "Terry Fritz" <teslalist-at-qwest-dot-net>
>
> > COOL!!  You beat me to it :o))
>
>But my C2 capacitor was very bad. Your realization will be more useful
>as a test of the concept.

I got it almost done:

http://hot-streamer-dot-com/temp/NewMag/0424-01.jpg

http://hot-streamer-dot-com/temp/NewMag/0424-02.jpg

Still need to mill up a little adapter to hold the top terminal and adjust 
the capacitance, but all the hard work is done.  If this becomes a "big 
deal", we will have to work on this HV-MMC thing to make it easier to 
build.  I had to call on to many 'tricks' to put his thing together.  Maybe 
a bit hard for the average person to make...


> > There are two schools of thought here.  Either the streamer length is
> > dependant on power alone such that John's spark length formula will still
> > hold true.  Or, that the much higher voltages of the magnifier will push
> > further streamers even if the power is held constant.  Past evidence
> > supports both.  No solid data to prove or disprove either.  Hopefully, we
> > will fix that ;-)
>
>The old questions of exactly what we want in the energy transfer to the
>resonator, apart from the average power, controlled by the primary
>circuit. How much voltage? How fast? How much topload capacitance?
>What quality factor in the resonator?

Lots of questions!  Hopefully, lots of answers real soon now ;-))


> > Yes!  And that is a bad place to be having a lot of series resistance.  My
> > coil will have a very low loss (hopefully) C2 so we'll see if that makes a
> > difference.  Capacitors getting hot deep in the power transfer section
> > could have a dramatic effect on streamer length!
>
>Flat plate capacitors without special insulation will always show
>corona around the plates, if not between the plates and the dielectric,
>wasting energy. I could put more capacitors in series, or design
>them so the electric field never exceeds the breakdown field in air.
>This would be difficult. I could make a capacitor totally encapsulated
>in solid dielectric (hot glue, for example). With everything
>optimized I would end with a homemade HV MMC...

I think you mentioned that you have trouble finding MMC caps and such in 
your location.  Feel free to ask you pals up here if you need any caps and 
such ;-)  Your only as far away as the post office!


> > That is interesting!  No other magnifiers have a separate C2.  Sort of
> > suggesting C2 is not needed.  However, maybe the C2 losses are so great it
> > is better off without it.  Hard to say which.  At least none of the
> > observed performance is worse than a two coil system.
>
>The observation of the waveforms with the lumped C2 disconnected
>shows that there is still significant C2 in the system. My secondary
>coil has more Medhurst capacitance than the resonator, and the
>resonator "seen from below" has to show some capacitance too (I
>am assuming Medhurst capacitance there too). I will make some
>mesurements to verify this. It's evident that a large magnifier
>may have enough distributed capacitance to dispense with a
>lumped C2.

Very significant!!  Large magnifiers seem to do better than small 
ones.  The naturally increased C2 on a large system may explain this!


> > If quenching is good without C2 and no quenching with C2, that could make a
> > dramatic difference too.
>
>This apparently happens.

Richard Hull's group liked to add extra series static gaps to his rotary 
gap system to help quenching.  There are many reports the quenching in 
magnifiers is a big factor....


> > Ok!  The L2 to C3 wire is always covered with corona.  The base of L3 is a
> > logical place too.  I am a bit surprised that the top of L2 is not a
> > problem but happy to hear if it is not.  Corona ring time ;-)
>
>There was some corona at the top of L2 too, specially at the screw
>ending the coil. The problem at the base of L3 was sparking between
>the bottom turn and the screws that hold the two plastic beads that
>hold the coil. Little sparks through the top holes of the beads:
>http://www.coe.ufrj.br/~acmq/tesla/mres4br.jpg

Ok, Corona rings should fix that stuff.  Apparently it is occurring in the 
expected areas.

>I will improve the fixation of the primary with the secondary, and
>adjust
>it precisely for the required k. I will also see what can I do about
>C2. Maybe study an MMC construction.

My C2 took a fair amount of effort, but it looks like it will work very 
well.  It will get a lot of good testing real quick now ;-))

Cheer's

         Terry


>Antonio Carlos M. de Queiroz