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Trev,
Performance is no better and no worse than what can be expected from any other sort of antenna of about the same physical size and the same length of feedline. Try it and see. I once worked 3 miles on SSB, on 160m, in broad daylight, with about 10 milliwatts, on 8 feet of wire lying on the ground, thrown out of a downstairs window. The ground connection was via 10 feet of wire from a domestic gas pipe. But I don't brag about it. The credit all goes to Clerk Maxwell. As Clerk implied, any bloody thing works. ---- Reg. ==================================== .. "Trevor Day" wrote in message ... In message , Walter Maxwell writes snip Just try to imagine what you bloody 'ole Brits could have accomplished around 1200 if you'd only had the tremendously high voltages achieved in the near field of a CFA antenna to hurl at the enemy. Walt Excuse me for 'jumping in' here, it was difficult trying to locate a bit of the thread that referred to the current title (CFA) I would like to ask you learned chaps a question about the 'EH' antenna which I appreciate is not the same as the CFA but its near enough for me:-) I have built a couple of these and used them on 40m. Performance hasn't been brilliant but they have worked and I was reasonably satisfied with the contacts achieved considering the fact I used a barefoot K2 at around 10 watts o/p and the antenna was sat on the shack bench connected to the K2 by a 1 metre BNC to BNC cable laid across the bench. (I only mention this last to try and forestall the inevitable comment that the feeder does all the work) All of this was done out of interest just to see if the antenna worked at all, as my gut reaction was, and still is, sceptical regarding the claims of its method of operation. I am not a mathematician, so the various lengthy discussions regarding Maxwell's equations et al pass me by; I am more interested in the practical aspects of this rather than the theory. My question refers to the SWR bandwidth achieved using this system. For an electrically very short antenna of this type I expected something extremely sharp at resonance, perhaps in the order of 5 or 10 KHz between the 2:1 SWR points. In practice, the 2:1 SWR points are some 100 KHz or so apart. When fed with 100 watts from an IC706, the antenna itself does not get warm and neither does the short feeder so it doesn't appear to be acting as a dummy load. Can someone satisfy my curiosity and tell me (drawing comparisons with springs and dampers if need be:-) how this is achieved. Thanks, Trev G3ZYY -- Trevor Day UKSMG #217 www.uksmg.org |