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Roy Lewallen, W7EL wrote:
"A short while ago, I explained why your Faraday cage doesn`t separate the E and H fields as you claim." n I am misunderstood. I never used the tem Faraday cage. I understand the Faraday cage to be a completely shielded enclosure which could be a metal automobiole body, a steel rebar reinforced concrete structure or a screened room. These all tend to completely block both the E-field and the H-field components of an electromagnetic wave. I gave an example of the metal rakes (Faraday screens) used at the medium wave broadcast plants where I worked. The function of the Faraday screen was primarily to eliminate capacitive cooupling, and thus the E-field between the transmission line and the antenna. This reduces harmonic radiation. It adds expense and complexity but is worth the price for lightning suppression if for nothing else. Most Faraday screens are used at powerline frequencies to eliminate capaacitive coupling between primary and secondary of a power transformer. I checked the internet for a recent posting and found an article by who wrote: "Beware, this cannot be an auto-transformer. It must be a transformer with two completely isolated windings, and with a Faraday Screen wound between the two." Why would one pay a lot of extra money for a transformer which eliminated capacitive coupling if it didn`t work, especially in Havana, Cuba? Best regards, Richard Harrison, KB5WZI |
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