More precisely, it is a device used in the transmission and reception of electromagnetic waves, without which we could not use existing telecommunications systems and, consequently, use all those non-wired (wireless) remote communications that we use daily.
There are 2 basic sizes that characterize each antenna and are represented by the gain and the directivity. The gain measures the power of the antenna, or more precisely its ability to concentrate the electromagnetic field in a given direction. The directivity instead expresses the ability of the antenna to select the direction of origin of the channel.
Their shape is very variable and closely related to the function they have to perform (telegraphs, broadcasting, microwave repeaters, radio telescopes, radar).
Where can I install an antenna? What materials do they make up?
You can install a satellite antenna or parabolic antenna:
- On a wall by means of special fixings;
- On the roof;
- On a chimney;
- On a pole adjacent to the house or isolated;
- On the terrace.
The antennas must be constructed with stainless and light alloy materials, so that they can withstand the atmospheric stresses. In general, they are made of aluminum or zinc-chromed and painted steel.
Tips for installing an antenna
Before you make the installation antenna there are some things to keep always well in mind:
- That there is sufficient space for a correct orientation of the parabola;
- That there are no obstacles (trees or buildings) that prevent them from being received;
- Avoid anchoring the antenna to chimneys, but it at least 2 m from them and in the winding position, in order to avoid the flue fumes corrodeing the fixing ropes or depositing residues on the elements, which can alter their properties;
- It is good to place it on the roof side farther from the road and away from the power lines, to avoid damage to things and people caused by a possible fall;
- The support pole must be absolutely vertical and well secured with clamps and special shelves so that there are no oscillations;
- If the antennas are more than one, it is necessary to have the most cumbersome and long ones at the bottom of the support, so as to avoid greater stress on the part of the wind (the lower antenna must still be placed at a height not less than 1.8 m);
- Approximately 1/8 of the length of the support (with a minimum of 40 cm) must be reserved for the anchorage of the same.
Planned tax incentives to install an antenna
There are no general application criteria to benefit from tax incentives on antenna installation operations. The incentives are laid down by the 2016 Stability Act (law 28 December 2015 No. 28), which gives the possibility to deduct 50% of the cost for the installation of the antenna.
The law of established 2016 states that a bonus, in the form of deduction rate irpef, it must be assigned to the “expenses incurred to carry out the extraordinary maintenance, the works of restoration and conservative rehabilitation and the renovation work of housing and the common parts of residential buildings”. In the expenses indicated, the installation of a condominium antenna in lieu of the private one.
As regards VAT, the rate is 10% as the one ordinarily foreseen for maintenance operations on residential buildings.
What rules regulate the installation of an antenna?
The rules governing the installation of antennas and electronic systems for the reception of radio and telephone broadcasts, as well as the passage of wires etc. are mainly found in 2 sources of law:
- D. LGs 259/2003 C.D. “electronic Communications Code”;
- The ministerial decree 37/08, art. 1, paragraph 2, point B laying down the compulsory technical requirements and the enabling of a technical manager for the installation of antennas and electronic systems;
- The law 66/2001, which deals specifically with the installation of antennas in condominiums.
If you live in the condominium You may also appeal to the so-called “right of antenna” established according to the jurisprudence by art. 21 of the Constitution, which guarantees the freedom of manifestation of thought and therefore also the right to freely access the information.
Right that has no real character, but personal, and that allows to accomplish all activities that are required for the installation of the antenna, which can in no way be banned.
A faculty that is so ensured to include, if necessary, the possibility of temporarily accessing the apartment of another condomino, provided that this happens in full respect of the other Condomino and trying to cause the least possible prejudice to the common goods and the exclusive property of others and possibly offering suitable guarantees for the realization of the autonomous plant.
You can find more information about installing parabolic antennas in a condo here.
What elements to consider when choosing an antenna?
When choosing and then proceeding with the installation of an antenna, it must be taken into account that the efficiency achievable is conditioned by both the characteristics of the antenna itself and a set of factors that vary depending on the situation.
The characteristics are defined by the gain (the ability to concentrate the electromagnetic field in a given direction), the angle of opening and the relationship between sensitivity in the direction of reception and the opposite.
While the external factors to be evaluated, among these 2 in particular:
- Structural factors: Characteristics such as: the height of the building on which the antenna is installed, the potential barriers (consisting of neighbouring buildings), the length of the plant and the amount of users;
- Reception factors: level of intensity of incoming signals, their wavelength and the possible presence of disturbances. It is good then consider considering the distance from the transmitting station, in fact more distant you find yourself from the transmission point more components, and therefore more gain, will have to possess the antenna. Another key element for receiving is the choice of antenna placement. Keep in mind that an antenna that has poor reception problems (because it is undersized in terms of gain or not enough directive) is an inconvenience that cannot be solved by installing an amplifier with high output level.
What type of antenna do you install?
There are various types of antennas on the market whose conformation is closely linked to the frequency band they have to receive. We therefore have antennas that can receive the entire spectrum of transmitted frequencies, antennas that can receive a single band or groups of bands, and finally antennas that can receive only one channel or groups of channels.
In general you can install antennas of three large macro-categories:
1. Yagi Antennas
It is the class of antennas that more than any other we recommend to use in the design and installation of the TV system, both for the greater power in terms of gain and for the greater versatility in the treatment of disturbed signals.
They are divided according to the reception of the signals in VHF and UHF.
For the treatment of the first you can find 2 models:
- Broadband (or Universal), which is capable of covering all frequencies of band III;
- Single channel, for the specific treatment of individual channels whose reception is particularly difficult.
For the reception of UHF signals, models are available:
- Broadband, able to receive simultaneously the channels of the band IV and of the V-band;
- Specifically or at frequencies of band IV or V-band;
- Narrow band, used for the treatment of groups of channels belonging to the same bands, but whose reception is particularly difficult.
2. Panel Antennas
This type of antenna is characterized by an average lower gain (although some models present on the market can reach 16 db) and for a much lower directivity.
-antennas are installed mainly for the reception of UHF channels, they are particularly indicated in areas where the signals of the repeaters come from different directions.
3. Logarithmic Antennas
They are made up of a series of dipoles in succession all fed. The dipole is the most important element of the antenna, the one capable of capturing the electromagnetic waves, of making available to its garments a voltage and to send it to the television system.
The longest dipole placed at the base of the antenna is a member of the reception of the lowest frequency, while the shorter one at the upper end defines the highest frequency. Thanks to this structure one determines what is one of the salient features of the logarithmic antenna: the constant gain on the whole range of frequencies.
They are also known as unique antennas as they are able to receive simultaneously the frequencies distributed on all 3 bands.
Installing a DIY antenna
First you have to go to a specialist shop in Antennistica and buy an external antenna. The ideal solution would be to find a complete assembly kit and other accessories needed to mount it, for example, on the roof.
At this point you have to choose the place of location. This is usually near the parapet of the roof and as high as it is possible to avoid interference with other antennas, and with any obstacles of architectural nature such as adjacent buildings, trees or advertising pylons.
Now take all your tools and go to the roof. Make sure you have everything you need, such as drill, wrenches and pliers, insulating tape and cable. At this point the work can begin.
We take the zinc pole that serves to raise the antenna and anchor it to the wall. Usually on the roofs there are always points of attachment of previous installations or predispositions for new plants. However, in the absence of them, you have to drill a hole in the lower part of the parapet (in the inside) and block with quick-grip concrete an iron bracket, which serves to pass inside the mast of raising the antenna.
Once the pole is fixed, the antenna can be hooked, it at the top with the appropriate clamp after the connection with the wire is made and with the amplifier supplied.
Once the antenna has been installed, it must be adjusted until the optimum signal is reached. The ideal is to bring a small television with you so that you can check the reception quality closely. However knowing the direction of the national repeaters and it following the antennas of the neighbors is easier to find the right position. When the optimal reception level is reached, the screws can be permanently locked so that the antenna remains stable.
Although in many people choose this solution, we think it is necessary to emphasize that resorting to “DIY” does not always lead to the expected results.
On the one hand because of the material used, often in fact, you buy antennas based on the experience of the shopkeepers. On the other you pay the lack of the necessary technical skills, but mainly of equipment, a field analyzer first.
It is not by chance that there are more and more people who prefer to ask a professional to get a quotation for the installation of an antenna. It is often worth spending a little extra to have a job done with precision and quality products.