Shortened YAGI antenna at 28 MHz. Scheme, description

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Shortened YAGI antenna at 28 MHz. Encyclopedia of radio electronics and electrical engineering

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Encyclopedia of radio electronics and electrical engineering / VHF antennas

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The antenna (Fig. 1) is a three-element YAGI with a director and a reflector, all three elements are made in the form of shortened helical dipoles.

Shortened YAGI antenna at 28 MHz
Fig. 1

Structurally, each of the elements is made of two ski fiberglass poles 1,5 meters long each, fastened together with a metal tube 10 cm long. 3 meters of insulated wire are wound onto the resulting pole 5 m long with a 2 mm pitch. The director and reflector are wound with a whole piece of wire, the middle of which is connected to a metal traverse. The feed element is torn in the middle. The antenna is tuned by changing the winding pitch in the middle part and moving the elements on the traverse.

This antenna, of course, loses to a full-size YAGI (as, indeed, any shortened one), but noticeably (by 1-3 points) outperforms a GP or a half-wave dipole.

Author: V.Karasev (RB5EHS); Publication: krasnodar.online.ru/hamradio

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