The performance of an aerial is mainly dependent on its type, size, use and height. If you are one of those people who think that you can enjoy better connectivity by installing it at a higher point, it’s high time you debunk the myth. Though the height of the antenna has critical impact on its performance, you have to consider other vital aspects like the radiation losses, feed impedance, radiation diagram and distance from interference.
Instead of installing the aerial at the highest point, understand the law of diminishing returns. Generally, broadcasters require high antennas or tall towers to get coverage at UHF and VHF. They try to achieve the greatest coverage area by increasing the antenna’s height.
Know the Antenna Height at Higher Frequency
It is advisable to mount the aerial close to the earth because of the signals’ wavelength at HF. The objective is to receive better electrical wavelengths. If the antenna is installed horizontally, the ground can interact with it in various ways.
Installing HF Antennas? Three Vital Factors To Consider
- Angle of Radiation
If you need HF antennas for long-distance communications, try to lower the antenna’s angle of radiation. Experienced aerial installers prefer installing it at half a wavelength. It is easier to get the right angle of radiation for frequencies above 15 MHz. Issues might arise if you need lower frequencies with longer wavelengths. Let the installer calculate the elevation for the horizontal antenna.
- The Ground
If you are installing HF antennas, first consider where the ground is. The signal might penetrate through the ground if it does not have a perfectly conducting surface. The degree of penetration depends on the type of soil and conductivity. It might even become a challenge for the installer to predict how things might work out. They also have to check the level of water in the soil before installation.
- Radiation Losses
Even if you are installing a horizontal antenna, make sure it is not very close to the ground. There might be radiation losses due to the ground. Very low heights can have a negative impact on the antenna’s performance. Generally, installers try to maintain a wavelength of around 150 metres for a 2 MHz signal. Ground losses often play a dominant role.
Get in touch with Aerialman and consider the points stated above if you want to install HF antennas.