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Re: Wireless transmission of power,

Original poster: Jim Lux <jimlux@xxxxxxxxxxxxx>

At 03:29 PM 3/17/2005, you wrote: 
Original poster: Ed Phillips <evp@xxxxxxxxxxx>

Original poster: "Lau, Gary" <gary.lau@xxxxxx>

This may be beside the point, but how the HECK do you build a secondary
to resonate at 8 Hertz?  What size topload?  Please give details beyond
"I hacked my secondary in half..."

Gary Lau
MA, USA"

Here's my design:

Cylinderical coil
Resonant frequency = 8 Hz
Coil diameter = 1000 feet
Coil length = 2000 feet
Top load is sphere of 1000 feet diameter, C =~ 6600 uufd.
Distributed C =~ 15100 uufd
Total C =~ 21700 uufd
L = 18,238 henries
Wire size = #10 (0.1 inch dia)
Wire length = 38,340,000 feet
Wire weight = 1,219,247 pounds
AC resistance = 38,298 ohms

Increase wire diameter to 1 inch
Wire weight = 121,924,700 pounds
AC resistance = 382.98 ohms
Winding factor =~ 0.53

Quite a coil and top load!  (Way, way bigger than Wardenclyffe!!!)
Tesla's world power system had a top load consisting of two concentric
spheres, one grounded, of the diameter of the earth.  I'll give the
d


Since we're designing BIG coils.. you might want to consider using aluminum wire for the primary: cost and mass. At 8 Hz, though, skin effect probably isn't as big an issue.

And, you need to do some power estimates too.. 1000 ft diameter sphere has a breakdown voltage of about 457 MV. We'll assume there's some surface imperfections that will limit it to, say, 100 MV.

The stored energy in the topload is about 33 MJ. We need to assume a reasonable break rate. Typical coils have break rates that are about 1000 times less than their resonant frequency, so .01 Hz for this one (assuming it IS a spark gap coil, right?) .. that's not too bad... only 330 kW average energy.