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From: Remy VE2AVV
Date: 29 Jun 1999
Time: 13:29:50
Remote Name: 132.209.6.142
Something seem unclear in my mind ( at least). Many articles talk about obtaining the same power with a large E field and a small H field or a large H field and a small E field. Of course the product E x H may be the same but in space, the H field is related to the E field by the equation H = E / n where n is the intrinsic impedance of free space and is equal to 377 ohms. This should mean that this proportion of E and H should be respected to obtain a kind of optimum EM waves or where am I wrong ?
It looks like putting to much of one field or the other just create reactive energy.
My other interrogation is on the claim that CFA or SuperC antennas work with high impedance so that the coils that feeds the top hat cylinder have low loss. The capacity of this cylinder with the close ground plate is a lot bigger than that of a quater wave antenna. These coils have to supply a great current in order to create a high voltage across the cylinder or ring and the ground plane. In this way, the losses in either the phasing coil or the loading coil is not small at all ans efficiency is certainly affected.
73 Remy VE2AVV