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First, the gain or efficiency of the dish will be lower than you estimate. The outer quarter wave of the dish is substantially lost to diffraction. This is a 26% loss of area. If it's centre fed, feed blockage will cost about 0.3 m² or another 10%, in practice double this because this is the best illuminated part of the dish. Then uneven illumination and ...


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How will you feed this dish? The feed antenna that comes on these antennas is not suitable for 70cm. The ideal feed antenna illuminates the dish and nothing else. To achieve such an illumination you'd want something like a Yagi or a horn antenna. After building such an antenna for 70cm and attempting to mount it on the dish, I think you'll quickly realize ...


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You had three separate questions there, I'll try to clarify some concepts: How can a time - varying magnetic field induce current in vertical strips Faraday's law of induction tells us how much there is electromotive force (a kind of sum of voltages that must be dissipated in the loop) along a conductive loop when a magnetic field passing through that loop ...


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It may be possible to use a conductive surface mounted on the outside of the rocket body as an antenna. Not knowing the dimensions of your rocket and without the benefit of any design equations, I used EZNEC+ to create a crude model of a cavity-backed cylindrical slot antenna: The "cylinder" is about 6.5-m tall and 920-mm in "diameter," ...


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You should use an antenna that is designed for the frequency of your RF module unless you have a compelling reason to choose a different antenna. A properly designed antenna will make the best use of the RF module's output power and avoid damage to the RF module. If you decide to use an antenna designed for a different frequency range from the RF module, you ...


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