the reasons and solutions for poor reception of satellite signals

In debugging receiving satellite TV or in use, it is often found that the quality of the received signal is not good, which is manifested as:

1.The signal is intermittent, and the picture sometimes has mosaics.

2.Disconnected, the signal is erratic.

3.The sound is intermittent, and the sound is turbid.

When these phenomena occur, some people tend to focus on aligning the satellite, thinking that the antenna is not aligned with the satellite properly, and spends a lot of time to adjust the antenna, but the result is still unresolved.

In fact, there are many reasons that affect the signal quality, which should be analyzed and eliminated one by one in order to satisfy the debugging and reception.

In debugging, first of all, the supporting equipment should be carefully inspected, and every link in the debugging and installation should be paid attention to,we can’t be in a hurry. We should understand and confirm the impact of the local environment on the quality of the received satellite signals, so as to avoid wasting all previous efforts.

Inspection of equipments

Digital Satellite Receiver

we should choose the receiver with stable and reliable,good after-sales service and brand reputation. Beginners should choose a receiver with signal strength display, low threshold and high picture quality,the function may not be very good,but it is required to be practical. Receivers with high thresholds often cannot receive signals when receiving weak signals, especially when the margin of other equipment is not very large, the threshold of the receiver is very important.For example, in the same supporting equipment, receivers with different quality are used, and poor receivers cannot receive weak signals, or the picture is unstable, with mosaic, etc

Antenna

Antenna is a key equipment that affects the signal quality. The accuracy of the antenna is very particular. Different brands of antennas,there are some antennas with very different advantages and disadvantages.

The quality of the antenna is poor or antenna is deformed, even if the antenna diameter is large,it will not help, the focus didn’t know where to go, and it turned out that the adjustment was not good,this kind of example has been heard from time to time.

In order to ensure excellent signal quality, the selection of antennas should not blindly pursue small apertures or superstitious large apertures, but pay attention to the accuracy and quality of the antenna. As for the size of the antenna, it only needs to meet the receiver threshold requirements of the received signal.

LNB

It is difficult to guarantee the quality of low-priced LNB, and each batch is different. The quality problems of LNB are mainly reflected in unstable working performance, such as local oscillator frequency drift and poor thermal stability, the consistency of the frequency band is poor, the gain is low, etc., in use, the signal will be unstable, some frequency bands are good, some frequency bands are poor, and even cannot receive the signal, the signal quality of low-gain LNB received is obviously not good.

I have done experiments, using the same antenna and receiver, receiving the same program, and replacing the LNB of different brands one by one, but It is found that the quality is not the same, even in different batches but in the same brand of LNB, there are still differences.so when debugging, we should know about the quality of the LNB used, it’s best to test it first.

RF cable and F connector

Although the cable and F connector are not the key equipment, if they are improperly selected, it will also affect the quality of the signal. If the core wire of the RF cable is too thin and the shielding net is too thin, the leakage and attenuation of the signal will be large, resulting in a decrease in the signal quality.

The connection between the F connector and the cable should also pay attention to the craftsmanship. If the connection is not good, it will cause a short circuit between the shielding net and the core wire, or cause the shielding net and the F connector to open circuit.

If the waterproof treatment is not good, the wind, rain and sun will cause oxidation, and the signal quality will be greatly reduced due to poor contact with the LNB.

So,in addition to the selection of high-quality cables and F connectors, it is necessary to pay attention to reliable connection and rainproof.

Various Switching Switches

When it is necessary to receive multi-satellite or multi-household reception, switching switches are required, such as: 0/12V, 13/18V voltage switch; 0/22KHz, DisEqc switch; various power splitter, line amplifier, etc. The quality of these switches varies, and the signal loss of inferior switches is very large, which seriously affects the quality of receiving. The selection of good switches is also very critical.

Conclusion：

In short, there are many reasons for the deterioration of the received signal due to the poor material of the equipment, and compared with high-quality equipment, the quality of the received signal is immediately reflected. The tuning process is often negligent, and the initial tuning of the satellite can not be adjusted well, so you should calmly think about whether these are the reasons mentioned above.

Installation and Debugging

1.After selecting high-quality equipment, the accuracy of the satellite is the first hurdle to determine the quality of the received signal, so you must be patient, especially for the initial adjuster, who are unfamiliar with the location and lack of experience. You can use some auxiliary equipment for satellite adjustment, such as: compass, satellite finder, inclinometer and so on. For experience in this area, it is best to read some articles about electronic publications, which must have the knowledge and experience introduction you need most.

2.Try to avoid debugging in rainy days when searching for satellites, because the bad weather will cause signal loss.You should also know whether there is sunspot interference during debugging and whether the cloud layer is too thick. Another thing to note is that even if debugging is performed in fine weather, the signal strength will be affected due to bad weather in the location where the signal source is transmitted, or the transponder that happens to be debugged is stopped, or the parameters have been changed, etc. Although this situation is rare, it is sometimes coincidental. For those who are inexperienced in adjusting satellites for the first time, they can use the time-sharing method or debug other transponder programs.

3.During debugging, avoid the obstructions in front of the antenna, such as houses, big trees, etc., you can use a compass, after determining the general orientation, visually observe the distance of the obstruction in front of the antenna. If it affects the receiving, you should move the antenna to change the position.

4.During debugging, a group of transponders with the strongest signal in the satellite should be selected, and then fine-tuned to the best point after receiving the signal, so that the weak signal can be received satisfactorily.

5.During debugging, we sometimes encounter nearby microwave interference, mainly in the C-band. There are indeed various microwave signals in the frequency range of 3.4-4.2GHz. When the microwave frequency is close, interference will occur, which is commonly referred to as co-frequency interference. In this case, the signal cannot be downloaded.

Conclusion:The various reasons for the above analysis are often encountered in debugging, so we must analyze them carefully, eliminate them one by one, and avoid detours.