Also an antenna site is necessary. This is not the usual conventional type of antenna. The array is designed to be built completely underground. Space for construction is necessary and may be any where from 100 to 1000 linear feet.
Due to the fact that we will be dealing with extremely long wavelengths on the order of miles rather than feet, you are going to need a little space. As long as you have a strip of property at least one hundred or more feet in length you will be able to detect the signals. There are several items of interest in determining your location. You will be building two arrays widely separated from each other. The further apart the better. Also if you have a choice, a damp location is better than dry rocky soil.
The first step in constructing your antenna/detector is to determine the magnetic orientation. Take an ordinary pocket compass and locate magnetic north. The line of sight between the two points should be aligned with North-South. The next step is to obtain some copper clad ground rods at least eight feet in length, put on some gloves and start driving one into the ground. "Helpful Hint" > We found that a standard metal fence post driver purchased from the local farm store was ideal for the job. It helps also to take a pair of post diggers and dig out a hole about 18" deep. Then drive the rod down into the ground below the surface of the hole leaving enough room to make a connection.
Next measure out a distance as far as possible, at least 30 meters (98 ft) in a North or South direction and repeat the procedure above, driving a copper clad eight foot ground rod into the soil. Then connect the two widely spaced rods together using a length of wire. Obtain an ohmmeter, and open the wire conductor and measure the resistance. Make a note of the reading, then reverse the ohmmeter leads and measure again. Then take this reading, average it with the other reading and you will have a close indication of the DC resistance between the two probes. (Ground Rods) Very likely unless you have excellent soil conductivity in your area, the reading will be several thousand ohms. The point is to lower this reading as much as possible. The lower the better. A workable resistance is 500 ohms however the ideal resistance would be around 5 to 10 ohms. In most cases however this would be unobtainable unless you used many ground rods or copper strapping at each end.
Keep adding rods at each probe site, spaced 20 feet apart from one another connected together with #6 copper bare wire, until the resistance gets down to between 25 and 500 ohms. Keep in mind two items. The further apart the probe sites, the lower the resistance, and the more rods driven into the ground, the lower the resistance. We have found that on the average, 5 grounds at each end of the site are sufficient to obtain this reading.
Another option rather than using ground rods, in rocky or extremely hard soil, you may use a ditch trencher and bury #6 or #4 copper wire at least 24 inches deep. The copper wire should be placed in an "X" fashion with a length of at least 25 feet. The lead cable will then be connected to the center point of the "X".
At this point in time, if you haven't given up and are still determined to build a ULF-ELF receive station, I have good news. The hardest part is over. Just one more step and your antenna system will be finished. This part of the construction is not complicated but should be built as instructed.
Obtain a length of CATV lead in wire such as RG-11 0r RG-59, from your local electronic parts store. A good source to try is the local Cable TV company. Sometimes they have lengths of scrap lying around their warehouse and will be happy to get rid of it. Connect the center conductor only, (not the outside shield) to each antenna array using copper clamps. Take each piece of co-ax to the location of your receiver. Then install a suitable connector to the two ends These two cables will be the input leads to the receiver. The shield should be connect to earth ground using a single copper clad ground rod. Do not use the power ground and make sure the ground connection is at least 20 feet from power ground.
Now lets take a look at the next
construction phrase which will be the actual building of the circuits
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