Very good antenna for both analogue TV and DTV, especially DTV as it outperforms cheap Yagi’s, Log, panel and other commercial antennas. It is designed for the UHF region, but above channel 54, the gain drops significantly. The antenna has 14dBi at its resonant frequency, and does not drop under 7dBi, with an average of 12dBi taken over all the channels.

Simulation

07 gray hoverman gain

Gain vs frequency

08 radiation pattern

Radiation pattern in Horizontal plane

Reflector can be made from net wire or with rods with similar performance. It is simpler to make it with rods. All rods can be made from any diameter and any metal, although the best results are achieved with higher diameter and more expensive materials, like brass. Copper is not recommended because it is very soft, and it would get bent by wind quite easily.

Construction

gray hoverman

10 gray hoverman

Fractal antennas are the latest and the most advanced designs. It uses self-similar designs and, as a result, one gets reduced antenna size (in comparison with classical antenna types for the same gain, or better gain per size, if you like) and better bandwidth. They can be used for all range of frequencies, but here we will explore the example that can be used for the whole range of TV broadcasting frequencies which is approximately 200-800MHz. The emphasis is put on the VHF, because UHF stations are usually more powerful and there are more VHF stations. Thus you would get equally good reception from VHF and UHF. Although any fractal can be used, the easiest to make is the Koch curve.

Simulation

01 fractal DTV antenna

Model in 4NEC-2 simulation software

02 fractal DTV Antenna 3D

3D Model in 4NEC-2

 03 fractal gain

Gain vs. Frequency

04 radiation pattern  05 radiation pattern 

Radiation pattern in Horizontal and Vertical plane

Construction

Construction details and Measurements are Available for Registered Users Only.

fractal antenna DTV Schematics

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