🚀 go-pugleaf

In article <1992Apr10.085039.10688@dxcern.cern.ch> jeroen@dxcern.cern.ch (Jeroen Belleman) writes:
>Can anyone suggest a method to measure the output voltage? I do not
>think suitable probes exist.

There isn't really an "output voltage."  The potential on
the sphere is a function of the charge it holds and the
capacitance between it and the grounds around the room.

>So far, I get fat sparks from a polished 4cm diameter metal pipe over
>a little more than 10cm. The more diffuse sparks from the pipe's end
>easily exceed 50cm. You can make you own voltage estimates from that.

Drat.  I forgot the breakdown voltages for air.  The
potential at the time of the spark is of course just the
distance (cm) times the breakdown voltage (KV/cm).

As you can see, by varying the capacitance (a smooth surface
nearby; a sharp surface at a greater distance) your generator
can operate at different potentials.

If you integrate the charging current to get the charge you
can determine the capacitance.

You should put the entire apparatus in a large faraday cage
(perhaps you can wrap the room in foil :-)) and measure the
total displacement current to get the net charge--this also
gives you a roughly calculable basal capacitance.

				--Blair
				  "Watch where you point that thing..."