In this field experiment telluric transference of electric power is tested in the medium frequency band (MF) at 1860kc over 110 miles. This is the final experiment for now in this series which uses a two-coil TMT (Tesla’s magnifying transformer) system where the transmitter and receiver are constructed with a primary and secondary coil. A new series of telluric experiments will be undertaken using a three-coil system where the TMT coils have a primary, secondary, and extra coil. With the two-coil system at 110 miles, and the ground electrode in the sea, no signal could be detected even when using a portable spectrum analyser with sensitivity down to -110dBm. In the overall series on telluric transference of electric power, the longest distance where a signal could be detected was at 27 miles in a natural lake, and where both radio and telluric-wave components could be measured as contributing to the received signal. Beyond this distance no further signal could be received, using the same TMT system in two very different coastal regions in the UK, at 70 miles on the south coast, and at 110 miles on the east coast. At up to 600W of input power at the transmitter, and a range of variations at the receiver, including with increased magnetic coupling between primary and secondary, no component signal was detected at 1860kc. Other signals could be received from transmitters in the surrounding region forming a control test that the receiver system was working correctly.
The video experiment demonstrates and includes aspects of the following:
1. Portable Tesla receiver (RX) setup and tuning, using a cylindrical coil tuned in the 160m amateur radio band, for radio-wave and telluric-wave field experiments in the far-field region.
2. Telluric ground connection using a submerged aluminium metal plate in the sea on the east coast of the UK 110 miles from the TX.
3. Small signal ac impedance measurements using a vector network analyser, to tune the RX Tesla coil to the series and parallel resonant modes.
4. Received signal measurement using a tinySA portable spectrum analyser, with input sensitivity down to as low as -110dBm across the band 1.5-2.0Mc.
5. Fine tuning to different modes using a telescopic aerial at the top-end of the RX secondary coil.
6. At 110 miles in the sea no result could be obtained down to -110dBm using the portable spectrum analyser, and no audible tone could be detected using the ICF-2001D radio receiver, at either the parallel or serial modes.
7. The spectrum analyser was able to detect signals at 1707kc and 1925kc from other distant transmitter sources, but showed no signal at the experimental frequency of 1860kc.
Video Viewing Note: The wind was very strong in this field experiment, and it is difficult at times to make out the audio, and hence this video is only a short summary of the key highlights of the experiment.
Two-Coil Telluric Transmission and Next Steps
This series of telluric experiments has used the same two-coil system from the close mid-field region at 18m up to the distant far field region at 110 miles, and has demonstrated that a very small telluric-wave component could be transferred between the TX and RX coils of the TMT system up to 27 miles distant. In these basic experiments we are using the earth as a form of telluric conductor or transmission medium, with emphasis on the lowest possible impedance at the ground system connection for both TX and RX coils, and establishing the longitudinal magneto-dielectric (LMD) mode across the cavity of the TMT system. In other experimental series such as High-Efficiency Transference of Electric Power, and in the Transference of Electric Power series, it has been demonstrated that a very high-efficiency of power transfer > 95% could be established in the close mid-field region with a single wire transmission medium up to 11m long. In this scenario it was conjectured that the LMD mode was well established and tuned across the cavity of the system, and it was demonstrated that the tension at the upper end of both the TX and RX secondary coils was very high, and a potential null point was established in the mid-point of the wire. In addition, a varying temporal phase relationship was measured between the voltage and the current along the length of the single wire, and with spatial phase coherence, a conjectured indication that the LMD mode is formed in the cavity.
When the single wire was increased to 30-40m long in the mid-field region the LMD mode was could not be properly established and a large proportion of the transmitted power ~60% was lost to radiation from the single wire in the TEM mode. In the comparative experiment in Transference of Electric Power – Single Wire vs Telluric ~45mW of power was transferred through a telluric channel 18m point to point between the ground system and connections, with 500W of power supplied to the primary of the transmitter Tesla transformer. It was conjectured that almost all of the transmitter power at 1860kc was absorbed into the ground at very close proximity to the ground system, and very little of the supplied power was able to reach the receiver Tesla transformer. This appears to be consistent with increasing distance from the transmitter, as the received signals become progressively smaller and smaller in the far field region. In Telluric Transference of Electric Power – MF Band 2-8 Miles at the first field location 2 miles from the transmitter it was possible to clearly receive with 6 bars of signal strength at only 10W TX power at 1860kc for the telluric-wave and radio-wave combined, and 1 bar for the radio-wave only. The attenuation of the signal at 1860kc under the ground appears enormous, and it was considered again that this loss is dominated by absorption of the transmitter power by the earth directly surrounding the main telluric ground system in the high medium-frequency band.
At the 8 mile man-made reservoir location, although the signal tone could just be detected at 10W TX power, it was necessary to use up to 400W of TX power to get reasonable signal strength up to 4 bars. It was also noted that the ratio of telluric to radio-wave components was around 1 : 1, and the far-field transmission distance had not significantly increased by going up to 8 miles at the transmitter frequency at the top-end of the MF band. It is considered here that the telluric channel/connection at the RX coil end was not as good as for 2 mile case, and especially in taking into account that the water-body used for the telluric ground was both man-made and may not be so well connected to the earth’s aquatic system. It is conjectured that the LMD mode was not established as dominant in the TMT transmission cavity, and that power reception at 8 miles was dominated by the TEM mode of far-field radio-wave propagation.
In Telluric Transference of Electric Power – MF Band 27-70 Miles it was been demonstrated that telluric transference of electric power was possible over 27 miles using a 1860kc cylindrical coil TMT system, although the signal was very small and could only just be detected. At 70 miles no signal could be received either from the telluric-wave or radio-wave. The results received were consistent with those obtained in previous telluric transference of electric power experiments, and also Telluric Transference of Electric Power – Brookmans Park AM Radio Transmitter, where it was demonstrated at 909kc that only ~ 50mW of power could be received at the Tesla transformer receiver 300m (approximately one wavelength) from a 150kW broadcast radio transmitter station.
So the overall conclusions from all these experiments so far in the telluric transference of electric power series are currently as follows:
1. The frequency of the generator in the MF band at 1860kc (and 909kc for Brookman’s Park) leads to very high power absorption losses in the earth close around the transmitter ground system, resulting in very little transferred power through the ground.
2. The tension or “pressure” exerted on the Tesla transformer receiver coil is extremely low even when connected to a ground node, natural water feature, or the sea, and only tiny amounts of power could be received and transformed into the primary circuit at the receiver.
3. The size, extent, and low impedance of the ground connection at both the TX and RX would be critical in the currently investigated telluric transmission in order to minimise signal loss at all stages of the transmission. This huge signal loss across all parts of the transmission medium implies that the TEM mode of transmission is dominant over the LMD mode.
4. This telluric sequence of experiments explores the ground as a simple “conductor” in the form of a single wire transmission medium between TX and RX, and it has been shown at the LMD mode could not be adequately established, or made to be dominate in the cavity of the TMT system.
5. These telluric experiments do not attempt to couple into the earth’s natural telluric currents, through the use of a modulated signal, and hence the high losses through the ground are equivalent to trying to transmit a normal broadcast radio signal in the TEM mode through the ground, which is well understood in electromagnetism to be subject to huge attenuation over only very short distances.
In view of all the experimental results gained so far it appears clear that the transmitter is not able to “push” the transmitted signal from the TX to the RX in the TEM mode through the ground, there is simply no mechanism for this which does not lead to very high absorption of the transmitter power in the earth. At close to medium far field distance the TEM mode can reach the receiver coil both through both telluric-wave and radio-wave transmission, and decays in signal strength over the distance as we would expect for a normal radio transmission. In all the telluric experiments undertaken so far it appears that the LMD mode has not been adequately established between TX and RX outside of the near mid-field region. It is conjectured that in order to establish the LMD mode between TX and RX in the far field it would be necessary to establish a coherent cavity between the two coils, where transmitted power can be “pulled” or “drawn” through the transmission medium to the receiver. It may be possible to establish this coherent cavity using a three-coil system employing Tesla’s extra coil at the transmitter and receiver, which is also a closer reflection of Tesla’s original magnifying transmitter system. It is further conjectured that the extra coil will assist in creating a cavity between the secondary and extra coil, and hence down into the ground system. It may also be possible to establish this coherent cavity by using a modulated signal to couple into the earth’s natural inner telluric currents, and hence the LMD mode established across the natural cavity of the telluric medium through a “resonant” synchronicity between the transmitter, receiver, and the earth.
The next steps are to explore transference of electric power both via single wire and telluric transmission mediums using a three-coil system, where both TX and RX have a primary, secondary, and extra coil. The design and tuning of a three-coil system is more complicated than the two-coil, as we now have two resonant coils which interact through a very short single wire between them, making them a pair of coupled resonators. Coupled resonators transfer energy back and forth between them, “beating”, which results in frequency splitting, and significant shifts in both the series and parallel modes of the resonant system. A study of the impedance dynamics of a three-coil system will be presented in a subsequent post, along with preliminary experiments on the single wire and telluric transmission properties. Modulation is also planned to be introduced, along with experiments at lower frequencies, and ultimately if possible down into the LF-band where Tesla was working with his own experiments. Lower frequency experiments present considerable challenges, including TMT size and scale, generator type and compatibility, radio regulation and licensing, availability of field locations, and resourcing and funding. If these challenges can be overcome then it may be possible to finally confirm or refute the possibility of high-efficiency telluric transference of power, and understand in much greater detail and accuracy the legacy that Tesla has left us to explore.
1. A & P Electronic Media, AMInnovations by Adrian Marsh, 2019, EMediaPress
2. Dollard, E. and Energetic Forum Members, Energetic Forum, 2008 onwards.