The idea was very interesting in the old days, since by looping part of the output back to the input, the gain of a single tube or transistor amplifier could be increased because the signal passed through several times, at the same time the selectivity increased because the feedback favored the tuning frequency. Of course the main problem was the triggering of autoscillations, and when radio hobbyists in the 30/40's had their antennas close together, they would interfere with each other. The reaction is not limited to the electronics, it also puts energy back into the antenna. This is a positive effect for reception, and not well known. The energy re-injected into the antenna opposes the received ambient field. The ambient field around the antenna decreases, but since the energy is conserved, this field energy is found in the input circuit of the receiver. So it is as if the antenna is acting on a larger volume of space around it, recovering more energy.
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"Open your mind, but not like a trash bin"
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