Below is described the design of the antenna with high gain for UHF reception. The antenna has a narrow beamwidth and a gain of G=22 dB. The width of the lobe in the horizontal plane is about 35°.
The painting of the antenna (see Fig.) looks like two spirals of copper wire with a diameter of 2...4 mm. as supports for coils used rods of suitable size made of Micarta or PCB with 127 mm drilled through holes for fixing orbits. The spiral can be made by winding copper wire on the pipe corresponding diameter (I used cans of paint). The rods are inserted with tension in the segments of pipe of appropriate diameter, welded to the end face to the reflector. As a reflector is used a sheet of galvanized iron size 500x800 mm.
Reconciling two antennas is carried out with the help of segments of coaxial cable RK-100.
Literature
- Eisenberg, A. F. Shortwave antenna. - M.: Communication, 1967
- Bunin S. G., Yailenko L. P. Handbook of Amateur radio-shortwave - To . Technology, 1978
Author: V. Bashkatov (USOIZ), Ukraine, Donetsk region, Gorlovka; Publication: N. Bolshakov, rf.atnn.ru