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Slick,
The only thing about making the 48 inch mast non resonant is what's on the other end of it? A ceramic insulator is not the same as a Radio Shack steel house bracket. Since it is behind the first reflector, probably doesn't matter in the real world. Tam/WB2TT "Dr. Slick" wrote in message om... "Tam/WB2TT" wrote in message ... If the second reflector is actually doing anything, which I doubt, you should be using a non metallic mast, and not bringing the coax down between the reflectors. Tam/WB2TT Actually, if you believe the yagi optimizer program, the second reflector is indeed not doing TOO much, but it does affect the back shape of the pattern, and improves the impedance bit, and also increases the dBd of the outer edge of the pattern by tiny bit too. And i did simulate having the mast at 48 inches from the DE, which i was advised was the distance where the mast would have the least affect. Changing the mast length in the YO program does affect the pattern shape though, so i tried to make the mast a non-resonant length. At any rate, we could probably survive without the second reflector, you are most likely correct, but maybe for the next design. It first, i considered having the "T" section of PVC pipe move outwards at a 90 degree angle, and then attach another section of 2" PVC that would be sticking out, so that the coax would be totally perpendicular to all the elements. But, this would be a bit unwieldy. Slick |