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Wayne,
The best study I've seen is in both the ARRL Antenna Handbook and in ON4UN's Low Band DX'ing Handbook. I think it was a 3 station that came up with a method (consistent with BL&E) that gave a simple formula for putting down the optimum number and length of radials, for a given length of radial wire available. I used that study to originally arrive at 50' long radials at 80m. This gave tip to tip separation of about 3 or 4 feet on 80m, which met his criteria. The material above specifically answers the question: how do you get the best bang for the buck for a given amount of available radial wire. Read that material..or at least get the formula and apply it to your available wire...that will get you were most of us are with respect to optimizing radials. Now, Reg has come up with his program that flies in the face of these other studies, indicating one can obtain comparable performance with MUCH shorter radials (5 metres instead of 16 metres) and that is what started this whole thread. We await some sort of comfirmation from several sources that Reg's numbers are correct. If they are, Reg will become famous. Currently here is how things line up: 1. BL&E doesn't seem to agree with Reg's numbers (on the issue of short radials) 2. Tom, W8JI's, recollection of his measurement don't either. 3. NEC-4 is in the process of analyzing the short radial comparability claim as we speak. The entire issue is: does the current in the radials described above taper off as quickly as Reg predicts, or not? If it does, the short radials will be comparable and Reg is right. If it doesn't, Reg needs to fix his program in that particular section. We await more data, or someone to extract from BL&E a precise answer to the actual question: how fast does current fall in a radial as you move away from the base of a 1/4 wave ground mounted vertical with shallowly buried radials. In the mean time, you can get started with the formula I referred to above. If Reg is right, you used more wire than needed. If not, you have your wire in place and are ready to go. ....hasan, N0AN "Wayne" wrote in message news:L0Nwg.5924$yN3.4270@trnddc04... These are very good points. I am reading these postings to try to understand the behavior of actual implementations that lie somewhere between the extremes you pointed out. In other words, what gets you the most bang for the buck.... How fast does performance change with increased radial length and number of radials. |
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