Why do we need to receive multiple satellite signals with one antenna
Although there are more and more satellites and satellite programs, the problem that comes with it is that many programs require more satellite antennas to be installed. For some people, the most trouble to install the antenna is that there is no place: some are not ideal, some are not allowed by the property, and some are not allowed to install on their roof by the homeowner for fear of the house leaking. One antenna is still reluctant, and the two are even more difficult. For others, it is not very economical to buy an extra set of antennas.
Now the satellite signals are very strong, so some enthusiasts with strong hands-on ability and quick brains came up with the idea of one antenna with dual satellites.
For example, the two satellites, Asia No.5 and Asia No.7, are only 5 degrees adjacent to each other, and they are both high-power satellites; many people hang a lnb next to the Asia No.5 antenna; after careful debugging, they can simultaneously receive Asia No.5 and No.7 satellite signals. But for ordinary users, on the one hand, how to debug finely and how to watch stably is a thorny problem that is difficult to solve. On the other hand, to add a high-frequency lnb, it is necessary to add a coaxial cable into the house; for ordinary users, it is also a very troublesome problem to drill holes through the wall and lead the cable into the room; what’s more difficult is that in many luxuriously decorated rooms, the cables are pre-laid; if adding a cable is very unsightly, re-laying is not easy to do. The use of holder brackets and high-frequency lnb can not only adjust the angle of the two high-frequency lnb to the best, and the installation is simple, but also different from the general one antenna dual satellites need to add a coaxial cable to the home, this set of products does not need to be added additional cables, only the original one cable can be done. This product adds an RCV cable interface to the newly added lnb. The product adds an RCV cable interface to the newly added lnb; when users use it, they only need to use a short cable to connect the original lnb to this interface, and then connect the lnb directly to the receiver, then it worked.
The working principle of this lnb is very simple. In other words, a 0/22KHz switch is added inside the lnb. The 22KHz interface is the RCV interface, and the 0KHz interface is directly connected to the lnb internally. Some readers may ask, since it is so simple, isn’t it the same for us to add a 22KHz switch? In principle, it is absolutely possible, but if you add a switch yourself, you would be afraid of freezing in winter and raining in summer, spring and autumn. How can it be safer than that of being installed inside the lnb?
We chose the BT-380 LNBF and tested it by ourselves. The installation is really simple and convenient. Just point the antenna at Asia No.5, install the new lnb next to the holder bracket, and use the one that comes with the lnb. The black coaxial cable more than 20cm long connects the two lnbs, and then connects the original coaxial cable to the other interface of the lnb next to it, and you’re done. It only takes less than 1 minute before and after. Note that when the receiver is inputting the parameters, the 22KHz switch of the Asia No.5 program is all turned on, and the Asia No.7 program is all turned off. The antenna we use is a 1.8M Bowei prime focus antenna. Whether it is Asia No.5 or Asia No.7, the reception effect is both very stable. Users in African countries can use the same method to receive Astra and Hotbird satellite signals, South American countries can Get a panoramic view of the Echostar and Galaxy satellites.
How to do it by yourself
Due to the limitation of reception conditions, how to use the existing conditions and equipment to receive multi satellites in one antenna is becoming the pursuit and dream of satellite TV enthusiasts. From the relevant publications, I have seen a lot of receiving experience of one antenna multi satellites, and I have learned that many fans have a lot of questions and disputes about the placement of the position of the lnb. Combined with our receiving practice, I will share my opinions with the fans .
1. For the reception of multiple satellites with one antenna, it is best to choose the satellite with weak signal as the main receiver, and the satellite with strong signal will be easier for both reception. For example, we use a 1.5M Bowei antenna to receive the 105.5°E and 100.5°E two satellites , and the 100.5°E satellite is used as the main receiver. According to the shift of the reflection focus, the BT-380 LNBF of the 105.5°E satellite is deviated from the focus. At a position about 3 cm to the left of the main focus (next to the main focus lnb as shown in the picture), the feed horn is slightly outward, so that not only all the signals of the 100.5°E satellite are full, but also similar to the single-receive 105.5°E satellite .
1. In the practice of viewing, it is found that the reflection of the satellite beam on the antenna surface is actually the main role of the individual petals (only the two ones close to the off-focus), and the reflected signals of other petals are very few. This may be the case when the main focus is used, but it cannot be the case when the main focus is used. Otherwise, the main focus will no longer be the main focus, but will be out of focus and become a partial focus. When the partial focus is used, the antenna efficiency will be reduced) This makes me I think if one or two petals are taken off, there should be no problem to receive ku band signals as long as the focus is accurate. Because only a few petals have more reflection signals, the off-focus lnb should be facing the petals, and if the partial-focus lnb is slightly outward or upwards a little, the signal would be best.
2. Regarding the selection of holder brackets: Since the antenna multiple satellites belongs to “abnormal reception”, the holder bracket are generally made by yourself. Like 100.5°E and 105.5°E, these two satellites are 5° apart, and the receiving antenna is small (1.5M), so the two lnbs must be close together, so I dug the left side of the 100.5°E feed plate a diameter and The diameter of the 105.5°E lnb is equivalent to the gap. Since the feed plate only works on weak signals, the feed plate is simply not needed for the 105.5°E satellite, so as to reduce the weight and facilitate fixing, and to receive the best signal with slight adjustment. The angle can be fixed firmly with iron wire. Of course, the majority of enthusiasts use their own brains to design better holder brackets.
3. In the past, some enthusiasts reported that the lnb of the combined signal should be placed on the left or the right, and how does the geographical location affect it. I drew a diagram based on the principle of beam reflection. The solid line represents the beam reflection path of the 100.5°E star, and the dotted line represents the beam reflection path of the 105.5°E star. The receiving point with a longitude of 113° is received in a certain place in Henan, and the receiving point with a longitude of 96° is received in a certain place in Sichuan.We can see that the left and right rotation of the lnb is not affected by the geographical location at all.
4. Asia No. 5 and Asia No. 7 are one antenna dual satellites feed plates. This type of plate is to cut a 7 cm diameter gap on the west side of the plate that was packed with the original lnb. Drill two holes with a diameter of 3 mm on the outer ring, make a semi-circle hoop, and fix the C head in the gap (note that it is on the west side, the position is very important!) In this way, there is no adjustment problem. Basically it’s a success. The reception effect of this kind of crash source disk has been greatly improved. The signal strength of the satellite receiver has not changed, but it is still 81, but the signal quality has greatly rushed to 89~97%. It is really easy to have two satellites on one antenna. Asia No.5 and Asia No.7 have a large signal margin.
Note: The signal of one antenna multiple satellites may be unstable, and the debugging process may be complicated. You need a lot of patience, ample time, and even physical strength. This kind of gameplay is only recommended for enthusiasts with a high degree of fever.
See the picture below, some multi-satellite holder brackets use universal thin angle iron, which can be freely combined and extremely convenient.
Bowei have 28years industry experience to manufacture lnb, antenna, cables and other microwave products; if you have any inquiry of these products, please contact us any time !