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              In the far eightieth years of 20 century, on to one of Russian radio 
                transmitting radio center I saw a self-made opened transmission 
                line that fed a transmitting antenna. Struts of the line were 
                made of oak tree. What is wonder at that? These struts were about 
                some tens years old. They were made 
                at the end of 40 years, during restoring of the USSR after World 
                War-II. The struts had been thoroughly boiled in paraffin before 
                installation. Till now these wooden struts, 
                made in great quantity, lie in a tub filled with paraffin. At 
                repair of transmission lines the paraffin is kindled, the insulators 
                are got and used. The wooden struts, despite of their "antiquity", 
                looked rather 'fresh' and had sufficient mechanical and electric 
                strength. 
               
               
              Figure 1 Wooden compression strut 
               
                
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              Made in the 
                USSR
                
               
                  
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              Figure 2 Two -wire line with usage of wooden compression struts 
              
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              The struts had length 12-15 centimeters, and width about 2 centimeters. 
                Kerfs were made at a small distance from ends of the struts. Figure 1 
                shows the wooden strut. Wires of the ladder line were wound around 
                of struts and kept on kerfs. Figure 2 shows the two-wire line with usage of 
                wooden struts.  
               
                
               
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