VHF antenna type YAGI at 144 MHz. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / VHF antennas
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Boris, OH5ZZ (UA1DJ) was able to learn about the design of a simple VHF antenna. According to him, the YAGI antenna is easy to manufacture, has good repeatability and is easy to tune.
The author of this antenna is OH5YW. He published her design in 1976.
The antenna can contain from 3 to 7 elements and has a maximum gain of 8-10 dB. Any insulating material is used for the bearing traverse: wooden slats, plexiglass, plastic tubes. Antenna elements are pieces of thin wire (3-5 mm) made of aluminum or bimetal.
All dimensions are shown in the picture.
The vibrator is matched to the coaxial cable using a delta-shaped open symmetrical matching line made of the same material as the antenna elements. The line outlets are securely connected to a continuous linear vibrator. The connection points are located symmetrically at a distance of approximately 11,5 cm in one direction and the other in relation to the center of the vibrator. The length of the line conductors is 19 cm, they converge almost at one point - at a distance of 0,5 cm, and are fixed on a small insulating platform. At this point, a standard half-wave balancing and matching U-bend from the same cable used for the descent is connected to the line input. It is desirable to place the delta matching device perpendicular to the plane of the elements, but it is also possible to place it in the same plane with them with an angle directed towards the director.
The antenna is a quick-detachable structure and, with a traverse made of improvised material, can be assembled in a shopping bag when assembled.
Author: OH5ZZ; Publication: N. Bolshakov, rf.atnn.ru
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