Vertical antenna on low frequency bands. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / HF antennas
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When working on low-frequency bands, a vertical antenna has a number of advantages. However, due to its large size, it is not possible to install it everywhere. Reducing the height of the antenna leads to a drop in radiation resistance and an increase in losses.
Radio amateur S. Gardner (K6DY / W0ZWK) applied a capacitive load at the end of the "Ground Plane" antenna on the 7 MHz band (see figure), which made it possible to reduce its height to 8 m. The load is a wire mesh cylinder.
A wire mesh screen and eight radial wires are used as an artificial ground.
The antenna is powered by a 50-ohm coaxial cable. The SWR of the antenna tuned with a series capacitor was 1,4.
Compared to the previously used "Inverted V" type antenna, this antenna provided a loudness gain of 1 to 3 points when working with DX.
Author: S. Gardner; Publication: N. Bolshakov, rf.atnn.ru
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