Re: grounding question

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Mddeming@xxxxxxx 

In a message dated 10/9/06 1:27:38 P.M. Eastern Daylight Time, 
tesla@xxxxxxxxxx writes:
Original poster: John <guipenguin@xxxxxxxxx>

If I cant drive a grounding rod for RF ground, what is this counter
pose under the coil I hear people mention?

Thanks,

     John.

Hi John,

    A counterpoise is a type of "virtual ground". consisting of 
foil, wire mesh (chicken wire etc.) or radial wires arranged in a 
daisy wheel at least as long and broad as the coil is high or the 
topload diameter, whichever is greater. This is placed underneath the 
unit with RF ground end of secondary attached to it. The topload 
"sees this as ground and all works. A foil one is cheapest and 
easiest, but wastes somewhat more power in eddy currents. Radial 
wires are the most efficient, but hardest to do and keep straight. a 
large square or circle of wire mesh is a good compromise. NOTE: 
During operation, the counterpoise is floating at unknown high 
potential with respect to earth ground. DO NOT TOUCH!!!!!

Hope this helps,

Matt D.