Plus the simple dipole in your example has a lot less RF coming back into the shack.
John KK9A David Gilbert wrote: There is only a fixed amount of total energy contained in all the lobes of an antenna. You almost definitely did get lots of lobes ... but you also got lots of nulls that exactly offset all those lobes. You just never heard the the hams that were in those nulls and they never heard you. Whatever you gain in one or more directions is sacrificed in one one or more other directions. This is basic physics. More lobes is not necessarily better. In fact, taken to the extreme it is self defeating because a very large number of lobes (assuming they were somehow all of equal strength as you stated) begins to approximate a unidirectional antenna with no azimuth gain in any direction. Just for grins I modeled your 700 foot antenna in EZNEC+ and on 20m it gave a maximum gain of about 9 dbi in a fairly narrow lobe at 16 degree elevation in both directions along the axis of the wire. It also gave a total of 36 other sharply narrow lobes arrayed symmetrically in all other directions, each with a gain of about 6 dbi. Between each lobe was a deep null of around minus 10 dbi. This was all at the same 16 degree elevation angle ... there were literally too many lobes to count on the 3D pattern, with lots of lobes and nulls at every azimuth and elevation angle. A simple dipole at the same 40 foot height would have given similar gain with a much broader lobe (both azimuth and elevation) in the two main directions, but of course without the multiple smaller side lobes. Three poles and two perpendicular dipoles would have given better overall single band results ... the only advantage of the long wire being that it gives a similar pattern along with similarly ugly match on multiple bands. Dave AB7E ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
