Re: BIG resonance! - thoughts...

To: tesla-at-pupman-dot-com
Subject: Re: BIG resonance! - thoughts...
From: "Jon Rosenstiel" <jonr-at-pacbell-dot-net> (by way of Terry Fritz <twf-at-verinet-dot-com>)
Date: Tue, 13 Apr 1999 12:07:06 -0600
Approved: twf-at-verinet-dot-com

Reinhard, all


<big snip>
>My question to you is: Why did (do) you use a 120ohm resistor and
>"measure" the current indirectly?. While it shouldn´t make a difference,
>I measure my NSTs with a DMM set to the 20Aac scale. The internal
>(DMM) measuring resistor on the 20A scale is very low (~0.1ohm or
>less), so the NST is effectively shorted and it won´t fry your meter. If
>I understood your setup correctly, you placed the NST, (cap), meter
>and the 120 ohm resistor all in parallel, correct? Did you do this
>(which is why I placed the word cap in parenthesis) during voltage
>rise (meaning the resocap now being connected) measurements,
>too?

Reinhard,
I measured the nst's output current like this because when I originally
started fooling with this stuff I didn't have an ac ammeter, only a
voltmeter.
I selected the 120 ohm resistor for two reasons: #1, it was a power
resistor,
and #2,(most importantly),  it was near the top of my used resistor can. Now
that I have a couple of DMM's I suppose that I could measure the current
directly instead of using this round-a-bout method.

My procedure to measure the output currents of the two nst's
consisted of the 120 ohm resistor and voltmeter across the secondary,
 I didn't have the capacitor in the circuit.  ( I just wanted to verify
that one nst was a 30mA, (unmodified), and the other was a 48mA,
(some shunts removed).

I tried some different value resistors in parallel with the resonant cap to
see if they had any effect which cap gave the highest resonant voltage.
It made no difference, the highest voltage still occured with the .005uF
cap, (on either xfmr). The resistors did pretty much kill the resonant
voltage
rise effect though.


Regards,
Jon Rosenstiel