WIRELESS ENERGY TRANSMISSION–SUMMARY STATEMENT
November 15, 2007
Hi Greg,
This thread is a continuation of the discussion about wireless transmission
using Tesla coils that shows up occasionally on the Tesla Coil Builders List.
It has to do with what some have called the "Tesla effect," the observed transmission of electrical energy from a Tesla coil RF transmitter
to a Tesla coil RF receiver. The question to be answered is whether the
energy is being transferred by ordinary radio waves or if some other mechanism is involved.
I believe if it can be shown that electrical energy from a Tesla coil transmitter can be received by a Tesla coil receiver, but cannot be received
by a radio receiver capable of detecting only radio waves then it will have
at least been demonstrated that ordinary radio waves are not involved in the
energy transfer process.
In my mind 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 being
propagated 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 is of insufficient strength to account for
the energy 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 involved in the transfer of energy can be shown by
testing the emissions of the Tesla coil transmitter following the guidelines
set out in "FCC Methods of Measurements of Radio Noise Emissions From
Industrial, Scientific, and Medical Equipment." If the Tesla coil
transmitter is found not to be a sufficient radio wave emitter to account for the energy otherwise received, then the
predominant connection between the Tesla coil transmitter and the Tesla coil receiver must be by some means
other than radio waves.
The radio wave emissions testing is to be done using a conventional radio receiver (with an antenna that is not grounded) that is tunable to the Tesla
coil transmitter's operating frequency, and which is sensitive only to radio
waves. 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.
A conventional radio wave transmitter connected to a dipole antenna as described above might be used to test the efficacy of the radio
wave receiver.
The basic assumptions behind this comparative study of a conventional radio
transmission-reception system and a 'Tesla wave' transmission-reception system are as follows:
1) The emissions associated with operating grounded 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.
Radio transmitters with tuned grounded or ground plane (counterpoise) antennas are also capable of emitting
the form of electrical 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 electrical 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 operating at
the same frequency, then the electrical energy from the Tesla coil transmitter that is well collected by the Tesla receiving transformer is not
predominantly 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 mechanism is involved.
Please see "Scaling Down Tesla's Wireless System for
Experimentation" for some additional thoughts on this subject.
Regards,
Gary
Gary Peterson
P.O. Box 2001
Breckenridge, CO 80424-2001
Phone: 970-453-9293 Fax: 970-453-6692
www.teslaradio.com
www.teslabooks.com
www.teslascience.org
----- Original Message -----
From: "Greg Leyh"
To: "Gary Peterson"
Cc: "Ed Phillips"
Sent: Wednesday, November 14, 2007 1:37 PM
Subject: Re: Wireless Energy Transmission Follow-up
> Hi Gary,
>
> Do you have a write-up summary of what you're working towards? I was cc'd
> on this thread somewhere in the middle. GL
>
>
> Gary Peterson wrote:
>
>> Ed,
>>
>> Thanks for your most constructive comments.
>>
>> You asked,
>>> What is your definition of "standard radio waves"? . . .
>>
>> By this I mean ordinary conventional radio waves. I generally use the
term "radio waves" in its narrowest sense, that is to say far-field electromagnetic waves that have closed back upon themselves, are no
longer associated with accelerating and decelerating charge carriers in the launching structure, and have their E and H components in phase.
These are the "Hertz waves" to which Tesla occasionally refers in his writings.
>>
>>>> . . . the next step is to address the antenna problem. Two different
types of antenna will be tried, a vertical dipole with loading coils, balun and antenna preamp and a tuned loop antenna also with a preamp.
>>
>>> How are you going to determine the mode of energy transfer? The two
>>> antennas will have different receiving area/gain and I don't see how
>>> you're going to be able to standardize them.
>>
>> The initial objective is simply to make the two radio antennas as sensitive as possible to ordinary radio waves.
As for subsequent calibration, this might be achieved, as you suggested, "by measuring the
strength of a signal from a distant station with each and using that ratio as a measure of the relative sensitivity."
This method is somewhat complicated by the fact that essentially all existing LF stations use
grounded antennas and thus the exact nature of their emissions is uncertain.
A dedicated reference radio-wave transmitter may eventually be required.
>>
>> As for discriminating between the different modes of energy transfer, minimizing the influence of the conducting ground by elevating the dipole
as far as practicable would help. The ground's influence might not be a
problem with the loop antenna, and inductive coupling might be minimized naturally by the relative 90deg orientation of the transmitting and
receiving elements. Also, placement of the ungrounded radio-wave receiver at the greatest possible operational distance from the Tesla
coil transmitter will reduce the electrostatic and magnetic inductive coupling.
Other techniques for minimizing the influence of ground also come to mind. . . .
>>
>>> . . . you're in an area here where rather precise measurements are
>>> needed and it's not clear to me that you have equipment suitable to do
>>> that.
>>
>> I do recognize the importance taking good measurements and am taking steps to make them possible.
While I'm not a rich person, I do have some resources to draw upon, am of simple means and am committed to making all
of this happen.
>>
>>> By the way, if you're using a tuned receiver to measure signal strength
>>> the transmitted waveform shouldn't matter as the signal received will be
>>> due strictly to the fundamental frequency component.
>>
>> The most obvious difference between the perfect radio transmission system
and the perfect Tesla transmission system is in the design of the launching and the receiving structures.
Reduced to the simplest form, the first is comprised of two dipole antennas in free space and the
second two top-loaded helical resonators both grounded at the bottom.
A less obvious difference is in the shape of the waveform used to excite the launching structure. While a sinusoidal waveform is good for the
production of ordinary radio waves, the proper performance of a Tesla transmitter is largely dependent upon the periodic introduction of an
abrupt pulse of electrical energy into the final oscillatory circuit.
>>
>> Regards,
>> Gary
>>
----- Original Message -----
From: Ed Phillips To: Gary Peterson
Sent: Saturday, November 10, 2007 5:19 PM
Subject: Re: Wireless Energy Transmission Follow-up
See notes. Not intended to be quibbles!
Gary Peterson wrote:
> Ed,
>
> You wrote, . . . As I understand your experiment you compared the receiver response to a short wire to that
with a resonant circuit attached . . .
>
> That's not an exact description of what I'm doing, which is 1) determining if a wireless connection can be established between a Tesla coil transmitter and a Tesla coil receiver over a distance exceeding a few wavelengths and if so, 2) is the energy propagated to some degree more or less by means other than "standard radio waves."
What is your definition of "standard radio waves"? Under
these conditions some energy is always propagated by other means.
Depending on their orientation the two coils will be coupled by their
mutual inductance and while that coupling may be small it won't be zero
either. There will also be some mutual inductance which can create
coupling other than through radiation. These effects are relatively
small of course while Tesla claimed essentially lossless coupling.
. . . and that's not a valid measurement since in the case of the
wire alone there was probably a large impedance mismatch and signal loss
while the matching might be much better in the resonant case.
> The reason for using the radio receiver alone with just an ordinary antenna,
that is to say, without the Tesla coil receiver existing as part of the receiver circuit, is to determine the "standard radio wave" output power
in the form of radio space waves of the Tesla coil transmitter.
The wire will pick up either radiated signals [if it's oriented correctly
with respect to their vertical polarization] or capacitively coupled signals
but in either case it's necessary to match its impedance to that of the
receiver input in order to get much signal. This is a simple electric
circuit problem independent of the mode which coupled a signal into it.
The most valid comparison you could make . . . is to compare the
absolute power received by a receiver [with impedance matched to the
antenna used] . . .
> I recognize the problem with the radio antenna used earlier. I now
have a fairly good Tesla transmitter and receiver pair; the next step is to address the antenna problem.
Two different types of radio antenna will be tried, a vertical dipole with loading coils, balun and antenna preamp and
a tuned loop antenna also with a preamp.
How are you going to determine the mode of energy transfer? The two
antennas will have different receiving area/gain and I don't see how you're
going to be able to standardize them.
> Whatever type of radio receiver antenna is used, it's important that it not be grounded.
Even the insulated counterpoise type of radio antenna may be unsuitable in this case.
Any receiver will have "grounding" due to the capacitance between the
case [and any attached leads] and ground. . . . under these two conditions:
1. When your Tesla coil is being driven with some specific power, and
2. When the same power is applied to an antenna with known radiation
properties and located at the same spot as the Tesla coil.
> As for operating a radio transmitter, I'll probably use a waveform generator as a low power transmitter to tune
up the dipole receive antenna. The main comparison being made is not between
the two different types of wireless transmitter (Hertz and Tesla), but rather between the two different types of wireless receiver.
The principle differences being in the design of the launching and the receiving structures, and the waveform, sinusoidal or rectangular, used
to excite the launching structure.
>
> Regards, Gary
Not trying to be difficult but you're in an area here
where rather precise measurements are needed and it's not clear to me
that you have equipment suitable to do that. I know I don't and I'm not
really sure what it would take. If your receiving loop is properly
shielded you can be sure it's not responding to external electric fields
but the output for a given signal, no matter how it's coupled, will
depend on such things as the diameter of the loop, the number of turns,
and also of its effective Q. It will respond both to the magnetic field
component of a radiated wave and also to the inductively coupled field
from the transmitter. By the way, if you're using a tuned receiver to
measure signal strength the transmitted waveform shouldn't matter as the
signal received will be due strictly to the fundamental frequency
component.
It occurs to me that you might possibly do some antenna
standardization by measuring the strength of a signal from a distant
station with each and using that ratio as a measure of the relative
sensitivity. The problem there is that, even if you try to orient each
so as to maximize the output signal, the differences in effective
polarization may introduce errors bigger than what you're trying to
measure. You're dealing with an extremely difficult problem here as you
realize and I wish you luck!
Ed