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About SATELLITE antennas
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What was A SATELLITE antenna?
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How does A SATELLITE antenna work?
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How does A SATELLITE flat antenna work?
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How is A SATELLITE antenna aligned?
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How large must a SATELLITE antenna be?
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Frequently asked questions about SATELLITE antennas
What was A SATELLITE antenna?
Everyone knows the oval or circular shapes, which are found in different shapes, sizes and colors. In general terms, these parts are also referred to as "satellite antennas". Technically, however, this is not quite right. The actual reception elements, i.e. the two antenna rods, are located invisibly and well protected inside the LNB. On our shop page with the LNBs we explained this in more detail.
The term satellite dish is more accurate and technically not wrong. The bowl is just a reflector surface. This can be made of glass-fiber reinforced plastic (GFK), sheet steel or aluminum.
Like a burning glass that redirects the sun's rays and merges them into one point, a satellite dish also works. Only that the focal point is in front of the reflector surface. And it is precisely at this point that the LNB is mounted. From there, the signal is routed via cable to THE SATELLITE receiver and then on to the TV.
How does A SATELLITE antenna work?
The external shape of the satellite antenna is of secondary importance for the function. Therefore, there are oval, round and partly also slightly square antennas. The curvature of the reflector surface is much more important. The must be designed in such a way that all the radio signals entering the surface are bundled in one point.
parabolic antenna;
The first SATELLITE systems for private TV reception or SATELLITE reception were still large, circular monsters with a diameter of over two meters. With these antennas, the LNB was still arranged exactly in the middle of the antenna. This design unfortunately has certain disadvantages, because the LNB and the LNB holder shade a part of the reflector. In addition, snow and foliage can easily accumulate in the lower part of the reflector, which significantly reduces the reception strength (see figure A).
Offset parabolic antenna
With the introduction of powerful satellites (Hotbirds), the reflectors no longer had to be so large, offset parabolic antennas were developed. For this purpose, only the upper area was used by a parabolic reflector (see Figure B).
This has the advantage that the reflector stands much steeper and thus does not find any grip on snow or coarse dirt. In addition, the LNB and the LNB support arm no longer have a shading effect (see Figure C).
How does A SATELLITE flat antenna work?
A special design for the satellite antennas is the flat antenna. This antenna bears its name, because here the receiving elements are integrated directly in the surface.
In contrast to a reflector antenna, which has only one antenna rod in the LNB for each polarization level, a large number of antenna bars are distributed over the entire area for a flat antenna. This is why these antennas are also called group antennas. This video explains the structure and the function.
How is A SATELLITE antenna aligned?
The different satellites are lined up on the geostationary track like pearls on a pearl necklace. The positions of the satellites refer to the zero meridian. This is a line that runs from the North Pole via London's Greenwich Observatory to the South Pole and is perpendicular to the Equator.
In order to correctly adjust the East/West orientation (azimuth), it is necessary to know the position of the satellite to be received and how far east (E) or west (W) one is from the zero meridian. In the west of Germany you are located about 6° east of the Nullmeridian and in eastern Germany about 15° east.
If° you° want to align a satellite dish with the satellite system Astra (19.2 E) in the Frankfurt area (approx. 8.5 east), you first have to align the antenna to the south on the geostationary track. The exact position is obtained by°° subtracting the own location position (e.g. Frankfurt 8.5 E) from the satellite position (19.2 E). As a result, the antenna must° be rotated from the south orientation by 10.7 toward the east.
The inclination of THE SATELLITE antenna upwards and downwards (elevation) also depends on the installation location. In southern Germany the reception direction is about 35° and in northern Germany about 27°. As a result, the satellite dishes are steeper in northern Germany (see Figure A) than in southern Germany (see Figure B). A scale is usually attached to the satellite dish's holder, which serves as a rough stop.
The fine alignment of THE SATELLITE system must then be carried out visually via image control on the TV or better with A SATELLITE finder. THE SATELLITE finder is switched in THE SATELLITE cable between the LNB and THE SATELLITE receiver. It is important that the antenna is only touched by the mast holder when adjusting. If the antenna is twisted at the reflector, it can easily deform, which was very quickly leading to a faulty measurement result.
How large must a SATELLITE antenna be?
The size of A SATELLITE mirror depends primarily on the illumination zone (Foodprint) of the satellite to be received. In case of doubt, the illumination zone can be researched via the image search on the Internet.
A satellite dish with a diameter of 60 cm is usually sufficient for the reception of the German-speaking stations of the satellite system Astra. However, in order to have a certain bad weather reserve for multiple subscriber systems, antennas with a mirror diameter of 80 cm or more are offered.
But as beautiful as a strong antenna signal from a large antenna is, the antenna must be mounted securely. A large reflector surface also represents a considerable wind load.
In case of doubt, consult a specialist before assembly.
Frequently asked questions about SATELLITE antennas
Can ich paint A SATELLITE antenna?
Yes, it is basically possible to spice up the reflector mirror with color, which is partly quite gray and dull, without worsening the reception on the TV. However, lead colors should not be used. The use of coatings with metal particles is also not recommended. As an alternative to painting, the reflector surfaces can also be covered with plastic adhesive film.
How many receivers can ich connect to A SATELLITE dish?
The number of receivers that can be connected does not depend on the satellite dish. Here the LNB plays the decisive role. We explained in our LNB guide which different LNBs are available and how many receivers can be connected. Experience has shown that the satellite dish of a multi-subscriber system should have a diameter of at least 80 cm.
What is the advantage of aluminum satellite dishes?
The main advantage is that aluminum is light and does not rust. A SATELLITE mirror made of steel sheet must be well galvanized and powder coated to be as durable as it is. From a reception point of view, it does not matter whether THE SATELLITE mirror is made of sheet steel or aluminum.
My SATELLITE antenna suddenly stops. Can the wind have twisted them?
Probably not if the bracket is still firmly mounted. Much more likely is an error in the LNB power supply. In case of doubt, you can unscrew the F-plug on the LNB and check the 14 or 18 V/DC with a multimeter. The cable between the receiver and the LNB may be open or short-circuited. In case of doubt, the LNB can be replaced for test purposes.
My new LNB does not fit in the holder, was what can ich do?
Older SATELLITE antennas had an LNB holder with a diameter of 23 mm. All new LNBs require a 40 mm recording. If no LNB adapter is offered for the existing antenna, it is cheaper to buy a new SATELLITE dish with a 40er LNB recording.