Text file for COILBLD4.GIF, graphical instructions for construction of high performance 1/4 wave Tesla resonators. 13) If the preceding directions have been adhered to, the completed Tesla coil (RF resonator) will closely resemble the diagram in figure 13. The coil form is hermetically sealed. There are no holes into the wall of the coil form. The wire never enters inside of the coil and all connections are made externally where they do not compromise the electrical integrity of the construction. The base wire has been cut, peened, and connected to a high current ground terminal. The other end of the coil, the air terminal, has been left untrimmed. 14) This shows how the air and ground connections are made to the completed coil. A stand-off insulator is placed on the top of the coil. A TOROID discharge terminal is placed on the insulator and the wire is air-wound around until it contacts with the bottom plate of the conductive toroid. These air wound turns are widely spaced, but the diameter is kept as close as possible to that of the secondary winding. Once contact has been made to the bottom of the toroid, the wire may be held in place with a small piece of tape, then the winding is discontinued and a bared section of wire is connected directly to the center of the toriod with a nut and bolt clamp, tape, etc.. Excess length may now be trimmed. The exact length of the stand-off insulator, and therefore the height the toroid discharge terminal sits above the secondary resonator, can only be determined by experiment. This varies with the size of the toroid, the size of the coil, and the input power into the system. Due to the number of factors involved, this insulator may require frequent adjustments/changes. For this reason I do not permanently mount a stand-off insulator on the coil. I keep a selection of square cut sections of PVC plastic pipe that I use for stand-off insulators. The toroid is elec- trically connected as indicated above, then it is simply set on top of a PVC pipe stand-off insulator. The system is now ready to be fired. If desired, after some experimentation, the insulator can be permanently mounted: the end cap should be scored with a sharp tool, not drilled; the surface should be prepared, and the insulator should be glued in place with two-part epoxy. The ground connection is made via the shortest available path, using the heaviest, widest possible SMOOTH conductor, to a dedicated RF ground constructed specifically for Tesla work. This ground is referred to as the "system RF ground" or simply the "system ground". The system ground is usually constructed, not happened upon. I advise constructing a system ground from scratch unless you can verify that any available grounds are electrically isolated. Do not use a water pipe. Do not use the house ground. Tesla rated grounds need to be extremely heavy, usually comprising of several eight to ten foot copper pipes hammered into the ground. The pipes should be separated in the ground by their lengths (eight foot pipes are set eight feet apart) and connected with one inch ground strap buried below sod level. It should be noted that these instructions are designed to produce a highly efficient RF resonator with exceptional electrical strength at the lowest possible cost. Coils built to these specifications are capable of producing, and withstanding, discharge lengths that exceed the physical length of the coil by a factor of 3.5 or more. These instructions are the product of years of experimentation winding dozens and dozens of coils and with the collaboration of others in the field of high powered Tesla systems. This design method has been repeatedly tested and reproduced by beginners with excellent results. This completes the COILBLD series on construction of high performance Tesla resonators. COILBLD4.GIF 6/9/95 Graphics and text prepared by: Richard T. Quick II 10028 Manchester Rd Suite 253 Glendale MO 63122 USA