Hydronic Radiation Transmitter
Radio-Electronics (May, 1967), p. 37-38.
“Build a Hydronic-Radiation Transmitter”
“Scientists in Florida have discovered a new form of electromagnetic radiation which propagates under water as well as radio does in air”.
“I must protest. Has a serious trade journal resorted to sensationalism? It appears that either that either a hoax is being perpetrated or that…”.
“A new mode of communications --- via underwater electromagnetic radiation --- is being explored by Hydronics Corp. Wallace Minto, inventor of the system, says signals have been transmitted over a distance as great as 30 miles by this method.”.
Is “hydronic radiation” a fact or a fraud? It has raised a storm of controversy as illustrated by the quotations above, all of which were written by responsible engineers or technical writers. The fact is that hydronic radiation does work. And the equipment is easy to build once a basic understanding of the new concept is attained.
But first, let’s see how the system’s inventor describes hydronic radiation. Wallace Minto of Sarasota, FL, desribes it as “a new vector field related to the electromagnetic and magnetohydrodynamic forces, characteristically propagated through a water medium and associated with electronic oscillations”. Translation: Hydronic radiation is the same as radio, except that it works through water instead of air.
Only the antennas distinguish the hydronic-radiation system from a conventional radio system. Receiving and transmitting antennas both have large plates, at each end of an insulating separator, to make contact with the water. A half-wave radio antenna has insulators on each end and radiates at right angles to the wire, as shown in Fig. 1-A. The hydronic radiation antenna appears to radiate off the ends of its plates (Fig. 1-B).
Early hydronic radiation experiments were made in the salt water of the Atlantic Ocean, and it’s in the oceans that the most exciting possibilities for hydronic radiation systems exist. Static-free communication between ships, dependable communication with submarines, and trans-Atlantic communication without cables have all been suggested by the concepts proponents.
But hydronic radiation also works through the fresh water found in lakes and rivers. As a matter of fact, the transmitter described here can be used in ordinary tap water to perform experiments in your bathtub.
When working in water, it’s dangerous to use AC-powered equipment; the transmitter, therefore, is designed to operate from a 9-volt transistor radio battery. Power drain is low, and the battery will last for many hours. The transmitter schematic is shown in Fig. 2. Q1 is the rf oscillator, tuned by L1 to transmit in the standard broadcast band, allowing use of an ordinary transistor-type AM radio as a receiver. Q2 is an audio oscillator, operating at about 1 KHz, which modulates Q1 through transformer T. The tone-modulated signal stands out clearly among the regular stations and thus makes testing easier.
The transmitter is built in a 5 x 7 x 3-inch aluminum box, with all components mounted on a perforated board except for L1 and the terminal strip. These are mounted on one end of the box. Standard construction techniques are used. And parts placement and lead length are not critical.
L1 is modified by winding a 25-turn coupling coil at its lower end. The two terminal marked TRANSMIT are used as the on-off switch. When the terminals are connected by a shorting wire, the transmitter will operate.
To test the transmitter, leave the box open and place a transistor radio next to the circuit board. Tune across the band and listen for the modulated tone signal. It should appear between 550 and 800 KHz. If you can’t find it, set the receiver dial at 550 KHz and tune L1 until the tone is received.
The transistor radio becomes our hydronic radiation receiver with a simple modification. Open the case and wind 25 turns of No. 24 enameled wire around it ferrite-loop antenna. Leave about 6 inches of wire at each end of the winding and twist the ends together to hold the winding in place. Bring the wires out of the case and snap the cover shut to hold them in place.
Two identical antennas are needed, one for the transmitter and one for the receiver. Fig. 3 illustrates the simple construction. End plates are 2 inches square, of 18-gauge brass cleaned to the bare metal to make good contact with the water. The 6-inch spacer can be of Bakelite, Lucite or other insulating material.
Two 6-foot lengths of plastic-insulated hookup wire are used for the feeder. One wire is connected to each plate by a solder lug passed over the end of the plate, then fed through holes in the spacer which allow the wires to be stretched taut. The rest of the wire is twisted together to make a balanced feed line.
Strip the enamel insulation from the ends of the antenna-feeder wires and from the two receiver leads, then solder them together. Tape the connections to prevent shorting.
Connect the second antenna to the transmitter. Place the antennas close together and check to see that the tone-modulated signal can still be heard at 550 KHz. Adjust L1 if necessary.
Final equipment checks should be made with the antenna in the water. A pool of water at least the size of a bathtub is needed, and the water should be a foot or more deep. Place the antennas facing each other about 3 feet apart. Retune the receiver to find the tone. It will appear at about 700 KHz (the water loads the transmitter heavily and shifts its frequency).
To make sure that the hydronic radiation signals are being received through the water, lift the receiving antenna out of the water. The signal should disappear or at least drop considerably in volume.
With the gear ready, we can perform a few experiments, to see how the system operates. A few questions may be answered, and a few more may be raised.
One of the interesting characteristics of a hydronic radiation communications system is the apparent directional pattern of its antennas.
Place the antenna underwater with the end plates parallel to each other. Rotate one antenna 90° horizontally or vertically so the edges o its end plates are perpendicular to the other antenna’s end plates. The signal will fade as you rotate, disappearing completely at the 90° position. As you turn toward 180° , the signal will come back and become strong again as the end plates once again become parallel. This experiment appears to show that the antennas radiate off the ends of the plates.
Antenna engineers, however, say, “No. The signal does not radiate from the surface of the plates”. Instead, they explain, the signal radiates from the wires that connect the plates. These wires actually form a dipole antenna; the plates, they say, are just “ground rods”. Furthermore, the signals so not go straight through the water at all. They travel from the transmitting antenna upward to the surface of the water, along the surface, then back down to the receiving antenna.
This description of hydronic radiation suggests that the behavior of signal radiation is opposed to our general experience. It is true that a horizontal-wire antenna will radiate its signal upward. The up-over-down theory implies that when hydronic waves reach the surface of the water, they must bend at right angles to travel along the surface. Then, when they are above the receiving antenna, they must bend downward to the antenna can pick them up.
The maximum distance for effective communication by hydronic radiation depends on the spacing between the antenna plates. The greater the spacing, the longer the range. Plate spacings of 1,000 feet have been used to communicate over several miles.
For our experiment, a plate spacing of 6 feet is convenient and will provide a range of 100 feet or more. The antenna will use a 6-foot 2 x 3 wood spacer and 1-foot square brass plates. The plates don’t have to be that big, but they must be heavy enough so the antenna will sink in the water (the wood spacer tends to float, of course). A good electrical connection is made to each plate, the connecting wires are brought directly to the center of the antenna and twisted to form the transmission line, which should be about 15 feet long. As before, two identical antennas are required.
The antennas should be placed about 50 feet apart in water at least 6 feet deep. With the antennas just below the surface and pointed at each other, the signal should be received loud and clear. Now, if both antennas are slowly lowered deeper into the water, the distance between them being kept the same, we observe an interesting result. The deeper the antennas go, the weaker the signal becomes. If we put the antennas deep enough, the signal disappears completely. Since the distance between the end plates hasn’t changed, we would expect the signal to become weaker as the antennas go deeper into the water. Since the signal is, in fact, weaker with the antennas deeply submerged, our experiment shows that the antenna engineers are right. The signal probably does go up-over-down.
Future of Hydronic Radiation
One experiment seems to prove that hydronic radiation travels off the ends of the antenna plates. Another seems to prove the signal somehow goes up-over-down. Is there an experiment that could prove that neither explanation is correct? If so, engineers haven’t discovered it. But there is no reason you can’t experiment with your radiation transmitter to see what conclusions might be drawn. After all, the las word on the concept isn’t in yet.
So far, experimenters are strongly divided on whether hydronic radiation actually is a different form of electromagnetic radiation that will prove useful in underwater communication systems. One cap holds that rf energy generated by the hydronic transmitter is radiated through water in much the same manner as it would be through the air, though with some differences. Obviously the circuits employed are identical in equipment used for both propagation media: air and water. The second group feels that there is some basically different phenomenon at work, one that promises efficient underwater communication.
Only extensive experimentation under carefully controlled conditions will provide the complete answer, of course. But, you can explore a phenomenon that’s in the news today, and do it with very little cash outlay. The hydronic transmitter does work; why it does isn’t apparent, at the moment.