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Steve,
You are right about the gain. I ran EZNEC on the 75 meter loop, and the gain at 40 m is about 3db more than on 75. However, it is not resonant in band. I got an impedance at 3850 of 40 + j5. Impedance at 7700 of 69 +j1, and impedance at 7300 of 18 + j87 (That is an SWR of 10). Gets worse below 7300. There is enough feedline and wire loss in the real world antenna that the SWR measured from the shack is about 5:1 on 40 m. Tam/WB2TT "Desmoface" wrote in message ... That was the whole point. 7700 is out of band. Tam/WB2TT Yeah, but its two wavelengths, it should probably perform at least as good or better on 40 than it does on 80?? It would most certainly have a lower angle of radiation. Again, I'm no electrical engineer, but I've always been led to believe that the bigger the antenna the better...it should certainly resonate efficiently on 10-80, in theory anyway..in the same way that a full wave is better than a half wave or a quarter wave. See: http://www.ku4ay.net/loop.html and http://www.cebik.com/atl1.html which are just a few of the sites discussing these fine antennas.. Steve kb8viv |
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