From: "B2"
Date: Wed, 11 Jul 2001 12:50:13 -0400
Subject: Re: [TSSP] Measurement of Topload Voltage
Hi Terry,
You could charge up the terminal of the Tesla coil with an accurate DC power supply through a big resistor of about 10 MegOhm. Once the voltage has stabilized then trigger an adjustable spark gap that would short the terminal to ground. There should be several signals present, mostly damped sines. One will be in the tens of megahertz from the direct toroid discharge. The others will be the secondary fundamental and harmonics. The only way to measure only the top terminal field, that I can think of at the moment, is to position the probe coaxially above the top terminal. Corona inception will alter this. Exploitation of the Kerr effect might help here.
An circular antenna flat on top of, and just above the inner flat surface of, a toroid. This may work well up to corona inception. A wire could go through a current probe inside of the toroid and then exit through an insulator to stick out a few inches from it. That way the field and corona current could be measured at the same time to get some idea of relationships. The corona would have to be directed away from the antenna to prevent space charge distortion effects.
Cheers,
Barry
> I am starting to like my plane wave antenna more all the time. :-))
>
> Perhaps I could charge the toroid and the other parts of the coil up
> separately and see just how much effect there is. I wonder if the antenna
> were in a "good" place it that would solve the problem.
>
> For a really different idea... I could amplify the output of the antenna
> and feed it to a fiber optic transmitter and use it in "reverse". In other
> words, instead of having the antenna far field measure voltage into the
> ground, it could be on the toroid measuring voltage going out. That may
> eliminate the effects of seeing the "average" fields of the coil...
>
> Cheers,
>
> Terry
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.