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![]() "Richard Harrison" wrote in message ... Richard Clark, KB7QHC quoted Mike Kalinski`s question: "What do you mean by equilibrium?" Richard also asked: 'How do you distinguish directivity from gain?" Only Art knows what he means by "equilibrium". Gain, however, is well defined by common usage and defined by experts. Gain and directivity are close relatives. Terman wrote on page 870 of his 1955 opus: "Directive gain depends entirely on the distribution in space of the radiated power. The power input to the antenna, the antenna losses, or the power consumed in a terminating resistance have nothing to do with directive gain. Such factors are taken into account in terms of power gain of the antenna which is defined as the ratio of the power input to the comparison antenna required to develop a particular field strength in the direction of maximum radiation, to the power that must be delivered to the directional antenna to produce the same field strength in the same direction. Unless otherwise specified the comparison antenna is a lossless isotropic radiator." I`m no longer completely in the dark about Gaussian antennas since finding pages from St. Andrews University about them on the internet. It`s an extension of optical principles used at somewhat lower frequencies in the millimeter and microwave frequency wavebands. All antennas can be scaled but are not always practical when made larger or smaller. Until Art comes clean about his ideas, we probably won`t know the likelihood of his success. Best regards, Richard Harrison, KB5WZI My first encounter with Gaussian antenna was with microwave relay paths and "fly swatter" antennas. A gaussian antenna is on top of the site building rof point straight up. the beam is then reflected in the desired direction by the fly swatter reflector that would be at about 300 ft up on a tower. In this case gaussian antenna meant a parabolic reflector antenna whose beam was further focused and cohered by a fresnel lens. No resemblence at all to Arts definition. Jimmie |
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