WIRELESS ENERGY TRANSMISSION INTERIM SUMMARY STATEMENT
"I am not producing radiation in my system; I am suppressing electromagnetic waves. . . . in my system, you should free yourself of the idea that there is radiation, that energy is radiated. It is not radiated; it is conserved." – Nikola Tesla, 1916
This INTERIM SUMMARY STATEMENT is a continuation of the discussion about wireless transmission using Tesla coils, showing up occasionally on the
Tesla Coil Mailing List.
It has to do with what some have called the "Tesla effect," the observed transmission of electrical energy from a Tesla coil
transmitter to a Tesla coil receiver as discussed in WIRELESS
TRANSMISSION THEORY. The question to be answered is whether the energy is being transferred by ordinary radio waves or if some other
propagation mode is involved.
If it is shown that radio receivers with conventional non-grounded or non-counterpoise radio antennas are more sensitive to radio waves than they are to the non-radiating electromagnetic field energy associated with operating Tesla coil transmitters, and also that the electromagnetic field energy associated with a distant Tesla coil transmitter is better received by a Tesla coil receiver, than it is received by such a radio receiver then it will have at least been demonstrated that some
propagation mode other than that of ordinary radio waves is involved in the energy transfer process.
Two steps need to be performed in order to demonstrate this. The first is to establish a connection between a Tesla coil transmitter and a distant Tesla coil receiver. A number of people have shown that this can be done. The second step is to show that the received energy is not propagating in the form of radio waves. This might be satisfactorily demonstrated by showing that a sensitive radio receiver, one which is capable of receiving signals emanating from a radio transmitter operating at the same frequency as the Tesla coil transmitter, is not able to receive a signal from the Tesla coil transmitter, and if a radio signal is present, that is of insufficient strength to account for the energy
that is actually received by the Tesla coil receiver.
The following is a general description of the experimental protocol.
First, place a tuned Tesla coil transmitter and Tesla coil receiver pair at a distance exceeding a few wavelengths and put the system into operation to demonstrate its functionality.
That radio waves are not wholly involved in the transfer of energy can be shown by testing the emissions of the Tesla coil transmitter, following the guidelines set
forth in "FCC Methods of Measurements of Radio Noise Emissions From Industrial, Scientific, and Medical Equipment" (see
http://www.teslaradio.com/files/measurements.pdf
). If the Tesla coil transmitter is found not to be a sufficient radio wave emitter to account for the energy otherwise received, then the connection between the Tesla coil transmitter and the Tesla coil receiver must be
at least in part by some means other than radio waves.
The radio wave emissions testing is done using a conventional radio receiver
and magnetic loop antenna, both tuned to the Tesla coil transmitter's
operating frequency. (It is this arrangement that interacts as much as possible with radio waves and as little as possible with the non-radiating emissions of
Tesla coil transmitters.)
The most appropriate antenna for this purpose is the ungrounded, balanced tuned
magnetic ferrite loop antenna. The tuned magnetic air loop antenna is also an acceptable type.
See Magnetic Loop Antenna Theory, http://sidstation.lionelloudet.homedns.org/antenna-theory-en.xhtml
for a summary of the physical rules defining the performance of small loop antennas used for VLF and LF
radio reception.)
A conventional radio wave transmitter connected to a balanced
tuned magnetic loop antenna is used to test the efficacy of the radio wave receiver and for calibration purposes.
An existing VLF or LF radio transmitter can also be used for preliminary
testing of the reference radio receiver. The problems with this approach are 1) the
radio transmitter will be operating on a different frequency, and 2) it will be using a grounded transmitting antenna.
The basic assumptions underlying this comparative study of a conventional
radio wave transmission-reception system and a 'Tesla wave'
transmission-reception system are as follows:
1) The emissions associated with operating grounded refined Tesla coil
transmitters are predominantly non-radiating with reduced emissions in the
form of radio waves.
2) Radio receivers connected to conventional non-grounded or
non-counterpoise radio antennas are more sensitive, to a degree yet to be
determined, to radio waves than they are to the non-radiating
electromagnetic field energy associated with operating Tesla coil
transmitters. Non-grounded radio antennas can be constructed, the
performance of which approach that of the perfect radio antenna.
3) Grounded Tesla coil receivers are more sensitive, to a degree yet to be determined, to the non-radiating energy associated with operating Tesla coil transmitters than they are to vertically polarized radio space waves. Grounded Tesla coil transmitters and grounded Tesla coil receivers can be constructed, the performance of which approach perfection in both cases.
4) Radio transmitters with tuned grounded or ground plane counterpoise antennas are also capable of emitting the form of electromagnetic field energy associated with operating Tesla coil transmitters and that radio receivers with this class of antenna are also capable of collecting the predominant form of electromagnetic field energy associated with operating Tesla coil transmitters.
It follows that: if the energy from a Tesla coil transmitter is well collected by a Tesla coil receiver, but not by a radio receiver connected to non-grounded or non-counterpoise antenna, while at the same time the radio receiver does collect energy from a radio-wave transmitter connected to non-grounded or non-counterpoise radio antenna, all of these
tuned to and operating at the same frequency, then the electrical energy from the Tesla coil transmitter that is well collected by the Tesla coil receiver is not
solely in the form of radio waves. If this is found to be true, the overall cause-and-effect relationships will shed some light on question of whether the energy is being transferred by means of ordinary radio waves or if some other
propagation mode is involved.
Please see "Scaling Down Tesla's Wireless System for Experimentation"
located at http://www.teslaradio.com/pages/scaling.htm
for some additional thoughts on this subject.
Note: Assuring that the 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.
In the case of dipole antennas the electrical length of the elements is
an important consideration. The overall length of a dipole antenna is about one-half of the 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 to eliminate as much as possible any electrical connection to the ground.
This consideration is based upon the knowledge that Tesla's wireless method depends in large part upon the passage of an electrical current through the earth between the transmitting and receiving apparatus, and that by breaking this connection the terrestrial 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
through capacitive coupling.
This leaves the vertical dipole antenna and the vertical balanced tuned magnetic loop antennas.
The dipole antenna may have some advantage in terms of efficiency, although this might be offset by the inclusion of the two loading coils
used to reduce its physical length. Furthermore, while the
predominant capacitive coupling between the bottom half of the dipole antenna and earth would be smaller due to the reduced area presented by the
lower antenna element, it would still be present to some degree.
This suggests the best form of radio-wave test antenna for this investigation is the magnetic loop antenna.