A half square antenna is a wire antenna that consists of two vertical elements fed in the phase. There are two ends of the half square wire, and one end is connected with the coaxial centre connecter while the other end of the wire is connected with the phasing line. Both of these segments are taken from the ground as you cannot take them from anywhere else.
The half-square antenna is broadsided, and it can exhibit a gain of 4 to 5 dB over a single and vertical radiator. The half-square antennas come in different lengths and sizes, and we have to choose the best length and size that can work perfectly for us. A 40-meter half square antenna is used most of the time as it has proved itself to be the best length for the half-square antennas. But unfortunately, you will have to select a suitable optimal height for the 40m half square antenna.
Many people are confused about the optimal HeightHeight of the 40m half square antenna as they don’t know which HeightHeight can be suitable for them according to the conditions. A half square antenna is a fundamental antenna, and it consists of two vertical legs of ¼ wavelengths, and all these are further connected to a horizontal wire of ½ wavelength. You can operate the half-square antenna without a ground plane. If you want to use the half square for low-end uses, we suggest you down point the half-square antenna because it can place a high current point at maximum achievable heights.
There is no certain optimal height for the 40m half square antenna as it depends on the surroundings. It can vary from place to place. If the soil is not better than the average, the antenna will fail to realise even if it is placed on the ground at maximum achievable HeightHeight. On 40m half-square, when the ends are near the ground, it will show its maximum gain, but the HeightHeight of the half-square will depend on the type of soil. If the soil is poor, you don’t have to worry as the 40m half square is not like the 80m half square as it works fine on poor soil. The difference is very marginal. If you set the 40m half square antenna at the height of 60 for the lowest point, the gain will increase continuously, and the take-off angle will be lowered.
If you are looking to work DX, you can set the 40m half square at 30 feet, but the heights are often not good for the low-end points and poor soils. You can achieve a low angle of radiations if the HeightHeight of 40m half square is just 7 or 8 feet. For building a half square antenna, you must keep in mind that the tail should not be more than ¼ wavelength as it is safe for both the animals and humans as well, and you should keep the limbs away from the tails as well.