| 摘要 |
In order to increase the bandwidth and to reduce the structural heights in a receiving antenna for very-high frequencies which is constructed in the manner of a coaxial antenna, especially for microphone signals which are transmitted by wireless means, it is proposed to fit two ferrite sections, having different 1/d ratios and an essentially low permeability, isolated from one another between the two metal tube sections. One of the two ferrite sections is surrounded by the coil windings of two associated LC resonant circuits which have different centre frequencies and are essentially not coupled to one another. Furthermore, the LC resonant circuits are in each case connected, via an associated decoupling coil, to a transformer which is connected to the coaxial connecting cable, which transformer transforms the overall impedances of the antenna, which are effective in the decoupling coils, to the characteristic impedance of the connecting cable, and carries out the reversal in balancing.
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