I am rebuilding a 40-meter loop antenna - the antenna is in the shape of a triangle with two points at the top of 37' telescoping masts and the third point of the triangle in a tree in the front yard. The wires slope down to the tree and stop about 8 feet above ground. The antenna has a balun near the top of one of the masts, a section of 75 ohm coax is in place between the balun and the 50 ohm coax to the station. I would also like to put up a 20 meter loop, either triangle, circle or rectangle shape. How far away from the 40 meter loop should the 20 meter loop be so that the two antennas don't cause interference with each other? Can I put the 20 meter loop inside the 40 meter loop? What happens if I put one leg of the 20 meter loop along the same point as the 40 meter loop going across the top from mast to mast? I would think some kind of coupling. I know that you can build fan dipoles for multiple bands. Is there a way to build multiple loops from one feedpoint?? (I know that quads are actually several loops, but I'm wanting to build a simpler one wire loop antenna. Any suggestions will be appreciate. Thanks.