WIRELESS ENERGY TRANSMISSION FOLLOW-UP
Those are very good questions.
Assuring that a radio antenna interacts properly with radio waves is accomplished simply by following good engineering practice when it is constructed and installed. Particular care must be taken in impedance matching the antenna itself with the transmission line used to connect it to the radio receiver. Another important consideration is the electrical length of the antenna elements. You are probably aware that the overall length of a dipole antenna is about one-half of wavelength of the radio wave that it is intended to receive. In the case of the low frequency radio waves (a.k.a. Hertz waves) the wavelength is so long as to be prohibitive from a practical point of view. For example, a 75 kHz radio wave has a wavelength of 4,000 meters. This means that a plain vertical dipole antenna cut to this frequency would measure almost 2,000 meters from end to end. Add 1,000 meters in separation upwards from the earth's surface to reduce its influence and the problem becomes obvious.
To assure that the radio-wave test antenna interacts as little as possible with the non-radiating emissions of the Tesla coil transmitter, the most logical step is eliminate as much as possible any electrical connection to the ground. This consideration is based upon the knowledge that Tesla's wireless method depends on the passage of an electrical current through the earth between the transmitting and receiving apparatus, and that by breaking this connection the current is greatly reduced. The use of a physically grounded one-quarter wavelength monopole Marconi antenna is, of course, out of the question. Even the use of an insulated counterpoise antenna is problematic due to the influence of the nearby conducting earth's surface. This leaves the vertical dipole antenna, the air loop antenna and the ferrite loop antenna. The dipole antenna may have some advantage in terms of efficiency, although this might be offset by the inclusion of the two loading coils needed to reduce its length. While the capacitive coupling between the dipole antenna and earth would be reduced due to the smaller areas presented by the two opposing surfaces, it would still be present to some degree.
As for firmly establishing the existence and further determining the behavior of the propagating, yet non-radiating emissions associated with the above-ground portion of operating Tesla coil RF energy transmission circuits, that is the primary purpose of this ongoing investigation.
Gary
----- Original Message -----
From: Matt D. Deming
To: Gary Peterson
Sent: Thursday, November 15, 2007 3:55 PM
Subject: Re: Wireless Energy Transmission Follow-up
In a message dated 11/15/07 4:57:15 P.M. Eastern Standard Time, Gary Peterson writes:
"The radio receiver's antenna must be configured in such a way so that it interacts as much as possible with radio waves and as little as possible with the non-radiating emissions of the Tesla coil transmitter. Some appropriate antennas for this purpose are the vertical 1/2-wave dipole antenna suspended high above the ground to minimize capacitive coupling to the earth, the tuned air loop antenna, and the tuned ferrite loop-stick antenna."
Hi Gary,
Still seems like begging the question: How do you know that an antenna is, in fact, "configured in such a way so that it interacts as much as possible with radio waves and as little as possible with the non-radiating emissions of the Tesla coil transmitter," until after the existence of such emissions has been established?
Likewise, how have you determined what "Some appropriate antennas for this purpose" are, until the behavior of these assumed emissions are established?
Now if a Tesla transmitter, properly shielded from any Hertzian waves, were to communicate efficiently with a Tesla receiver, also properly shielded from any Hertzian waves, then we would really have something to talk about!
Matt D.