DescriptionPSM V63 D117 Various forms of marconi antennae.png
English: Various forms of wire antennas used with spark-gap radio transmitters during the early wireless telegraphy period of radio, from 1887 to 1917. The energy of the waves emitted by early spark transmitters depended on how much electric charge could be stored on the antenna. So to increase the capacitance, large multiple parallel-wire antennas were used. These were long wire monopole antennas supported from towers (not shown). They transmitted in the medium wave and longwave bands, below 3 MHz. The types are: (a) simple vertical ((b) cage antenna (c) fan or harp antenna (d) another cage antenna (e) inverted umbrella antenna
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