Note also that resistance to RF is one of the variables that have to be factored in the overall impedance of an antenna. In your case, in Alabama, ground conductivity is considered good on average.Ģ- ohmic resistance of wire to RF energy at a given frequency and power level is a function of wire size (skin area) and quality of outer skin. Please note that there is a difference between:ġ- radiation resistance - called feed point impedance - is a function of physical length of antenna at a given frequency, position of the feed point on the antenna, height above ground and ground conductivity (for RF) below. Just to make sure that we are on the same page. Your concern is: radiation resistance of each dipole at 70' above sandy loam in Alabama. to answer your query properly would take a whole book! :) There is so much to take into consideration that. Now you are asking which of the following antenna wires is best: stealthiness (not a concern in your case I assume ) frequency of operation (overall unsupported span of the antenna wire) The following must be considered as they all play a part on the resulting performance: The improved receiving capability of the new antenna will readily become apparent, all else being equal.įirst I should tell you that the choice of antenna wire depends on the application. It involves taking down the old oxidized dipole and - immediately - replacing it with a new antenna of the same dimension and made of new copper wire, and installed at the same height. However, the big difference will be noticeable on receive.Īn increasingly large portion of the scant microvolts of RF - that the antenna manages to capture - will be lost due to the resistive oxidized copper coating (skin of the antenna wire).Īny ham can easily test this. In spite of this degradation,it will still continue to radiate enough RF energy to make contacts. Generally they use aluminum-clad steel wire !Ī resonant HF dipole made of bare copper wire will oxidize over time. #WHAT IS THE BEST GUAGE WIRE TO USE FOR SHORTWAVE ANTENNA DOWNLOAD#Or if you not convinced, try to download some antenna specs from these companies and you will probably find a definitive answer. #WHAT IS THE BEST GUAGE WIRE TO USE FOR SHORTWAVE ANTENNA PROFESSIONAL#consult with professional HF antenna designers from some serious companies ( TCI, Grainger, Telefunken, Thomson, Brown Bovery, etc ) and ask them why they NEVER use copper (not coated) as antenna wire.ħ. you will make probably more DX contacts.Ħ. Put any piece of oxidized metal as antenna when the HF propagation is wonderful. DX will still be very difficult to obtain, if at all.ĥ. #WHAT IS THE BEST GUAGE WIRE TO USE FOR SHORTWAVE ANTENNA INSTALL#Even if you install the best state of the art HF antenna at 200 ft above ground, made with gold or silver wire and pure diamonds as insulators. is a very big challenge for a ham radio operator.Ĥ. Measuring HF antenna properties ( H-V pattern, directivity, radiation efficiency, polarisation, etc. You are not able to verify how your antennas are degrading in performance over the years, because the evaluation is directly related to the HF propagation and not to the antenna itself.ģ. Using copper wire as antenna during 40 - 50 years without any problems, is not giving a true answer of the problem, because you are not able to measure the radiation efficiency of your antennas. Any physics/chemistry book and any engineering book on semi-conductors will explain why.Ģ. Generally speaking, metal oxide is not a good conductor.
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