Re: Van de Graaf and 3/4" grounded sphere (fwd)

[Steven Roys <sroys@xxxxxxxx>]

---------- Forwarded message ----------
Date: Sat, 10 Jan 2004 18:54:27 -0600
From: Dr. Resonance <resonance@xxxxxxxxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>
Subject: Re: Van de Graaf and 3/4" grounded sphere (fwd)


With most Van de Graaffs, maximum impact is delivered with a ground terminal
33% x HV term. dia.     This gives a high capacitance value and delivers
very fat, bright sparks.  Smaller terminals deliver longer sparks but with
considerably less energy.  You can use 6-12 inch dia. smooth copper plumbing
floats available from McMaster-Carr Supply Co., Chicago, IL.   They work
great.

Using this 33% formula, output potential works out to approx 26.5 kV/inch of
bright spark length.  Ignore the long thin streamers as they usually emit
from sharp and not large rounded objects.

Dr. Resonance

Resonance Research Corporation
E11870 Shadylane Rd.
Baraboo   WI   53913
>
>
> You will find that your results are actually being limited by the fact
> you are using a 3/4" grounded sphere.
> If you increase the size of that grounded sphere, you will greatly
> increase the length of your discharge.
>
> Dan
>
>
> > > Best results to date with pumping are about 18" discharge
> > to a grounded 3/4"
> > > ball.   I have tried the blowdryer trick to remove moisture
> > but with the
> > > polyethylene belt is tends to grow in length and become too slack.
> >
>
>
>