ANTENNA LOW-NOISE Q SPOILING CIRCUIT

摘要

Input coupling circuit for detuning the Q of a high-Q ferrite rod antenna. A high impedence low-noise amplifier (4) is used to amplify the output signal from the LC resonant tank (L1, 1) of the rod antenna (M). A portion of the amplified signal is fed back directly into the magnetic circuit of the antenna tank. This negative feedback reduces the losses produced in the magnetic circuit due to the presence of nearby conductors. As a result of this reduction, an increase in the antenna sensitivity and a decrease in the cross-feed from other nearby antenna is produced.