Re: SV: NST resonance - Terry's testing

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

Original poster: "Malcolm Watts by way of Terry Fritz <twftesla-at-uswest-dot-net>" <m.j.watts-at-massey.ac.nz>

Hi Terry,

On 13 Feb 01, at 12:09, Tesla list wrote:

> Original poster: "Terry Fritz" <twftesla-at-uswest-dot-net>
> 
> Hi Jan,
> 
> At 06:59 PM 2/12/2001 +0100, you wrote:
> >Thank you for probing my results, Terry!
> 
> No Problem, that's what make this stuff so much fun!  I too was very
> surprised it worked out so well.
> 
> >
> >As your results came so close to the theoretical value I think we
> >have to assume that yours are correct. I must have made a serious
> >measuring error or my transformers are weird, or both. 
> 
> I hesitate to say my test was the final word but...
> 
> >
> >Perhaps my NST:s contain power factor correcting condensors, as was
> >suggested on the list. I will try to get manufacturers data for them.
> >I have thought a bit about my makeshift voltage divider network, used
> >instead of a regular HV-probe on the secondary side. Perhaps I went
> >over the top with the resistor values and invited all sorts of non
> >wanted signals to sneak in by capacitive coupling.
> 
> If the NST has one of those internal caps with a separate primary
> winding, that may do all sorts of strange things.  An external PFC cap
> should be invisible if the voltage supply has very low impedance.
> 
> High voltage dividers are very susceptible to tiny stray capacitances
> which can really mess up the tiny currents and such in dividers
> (especially at the higher frequencies).  High voltage probes go to
> great lengths to get all the stray capacitances just right.
> 
> I still wonder about the impedance of the driving amp.  You may try
> loading it down with a low value resistor just to verify that it is
> able to drive low resistances without drooping.  the inductance of the
> transformer may also confuse some amps.
> 
> >
> >I will try to review my measurements later this week, but for now I
> >think we should look upon Terry´s as the correct ones. It really is
> >very satisfying if measurements coincide with the theoretical models,
> >as Terry´s do!
> 
> Yea.  It is one of the few experiments that actually seems to have
> worked right the first time :-))  I was not sure if it would work
> right or not especially with only 1 volt input.  I worry a bit because
> it seemed to work almost "too" well...
> 
> Cheers,
> 
>  Terry

Despite what I said earlier, I first measured NST/cap resonances 
using the same method a few years ago and can confirm that your 
results mirrored mine.

Regards,
Malcolm