Re: Gap voltages AC vs. DC
Reply To: gomez-at-netherworld-dot-com
Sent: Saturday, January 03, 1998 3:55 PM
To: Tesla List
Subject: Re: Gap voltages AC vs. DC
D.C. Cox wrote:
> to: Adam
> Did the machine bolts have only a 180 degree circular area? If so, the
> sharper edges would disrupt the electric field and skeer the results.
> Even in the spark jumps over the rounded area the electric field can be
> modified by the sharp edges within 3-4 (ball) diameters and give you
> readings. Try a true sphere is possible and the results should be closer.
Absolutely. Also, even the material the spheres are made from (ie, brass
vs. aluminum vs. iron and its alloys) makes a difference in precision
measurements, as they have different emissivity. Then there are the
issues of temperature (warmer air breaks down earlier, warmer spheres
emit more electrons), pressure, humidity, etc, all of which have to be
controlled if you want to collect meaningful data.
Oh yes, and if there is any current at all behind your source, every spark
will leave a tiny mark on the sphere, possibly causing a divot that will
emit more than a perfectly smooth sphere. This is why Ross Engineering
sells precision measurement spark gaps with optional carbon spheres.
(no, they ain't cheap)
Gomez: card-carrying mad scientist, extreme fetishist, fiction dabbler,
pyrophiliac, technomage, goth, SF fan, lighting designer, dominant
pervert, and juggler of labels... http://www-dot-netherworld-dot-com/~gomez