Author: Tianzek
Be
Below, there is an example of 118.04 ° East, 36.9 ° Northern Wei 36.9 °, receives 138 ° E Asia Pacific No. 5 satellite KU band "Great Wall Platform" on the "Great Wall Platform" as an example. 1. Select (1) receiver. In general, the program receiving the Sino-Star Nine requires a dedicated receiver using ABS-S. Only, this machine is non-selling, so it is almost all the cottage goods seen in the market. Buying this product must take into account whether it is possible to pay the future frequent "upgrade" problem and how long the free signal on the in Nine. Receive other Chinese broadcast satellites, such as Zhongxing 6B, Asia 3S, Asia Pacific No. 5, New Day 11, Han Xing No. 5, etc., then the general DVB-S system receiver is required. There are many brands in this type of receiver market, and there are common, Tongzhou, Tiancheng, Zhuo Yi. Among them, Tiancheng's power consumption, stable work, low price, and thus the price is relatively high, can be used as the preferred family.
Of course, a model called dual mode receiver has occurred in recent years, which can receive both ABS-S signals, and can receive DVB-S signals, and the price is only 67 yuan, and the effect is also possible. In addition, in order to find the show, it is best to choose a product with a blind function.
(2) Antenna. Commonly known as "pot", positive feednother, fed. The feedback antenna is large, and there are two types of 1.2 meters diameter and 1.5 meters: generally used for reception of C-band signals: a small amount of the antenna, a common 0.3 m, 0.45 meters, 0.60 meters, 0.75 meters and 0.90 meters, generally used for reception of KU band signals. Due to the high price of brand antennas, the market is almost clear, the market is almost clear. Although the miscellaneous goods is inexpensive, there is a problem with light use, and the size is not accurate, the reception effect is poor, and the life is limited. Therefore, in order to improve the reception effect, as long as the conditions are allowed, select the large caliber product. When you select the feedback antenna, you should carefully observe whether the projection of the circular holes on the stent used in the high frequency head is in the antenna, otherwise it should be adjusted. When selecting a feedward antenna, it is necessary to carefully observe whether the projection of the high-frequency headridge (referring to the single rod antenna) is on the left and right flat lines of the antenna, otherwise it should also be adjusted. The position of the antenna focus can be corrected if necessary. It is selected here that a three-dimensional biasing antenna of ordinary 45 cm is selected.
(3) High frequency head. The high frequency heads seen on the market also have genuine-including high frequency heads and KU bands of the C band. The receiving band of the C-band high frequency head has only one, namely 3.4 GHz, 4.2 GHz, and the local oscillator frequency is 5150 MHz. There are a number of receiving ranges of the high frequency head in the Ku Bode, and there are two types of 11.7 GHz to 12.25 GHz and 12.25 GHz to 12.75 GHz, and the local vibration frequency is 10.75 GHz, 11.30 GHz. No special needs, do not choose a single polarization high frequency head. In general, the difference between the circular polarization and the linear polarization is only in that the polarized tablet is inserted in the resonant cavity. Here, it is the high frequency head of the Nanded GKF-3301 type Ku with a total GKF-3301 type of the receiving frequency range of 12.25 GHz to 12.75 GHz.
(4) Coaxial feeder. There are two kinds in the market. One is copper heart, one is iron-based copper. To work reliably, you should try to choose the copper core line. Although the iron core wire is inexpensive, it is often frequent due to the fault of rust. This should be paid to this in wet southern regions and coastal areas.
2. The connection receiver of the receiving equipment, the television, and high frequency heads must be correct and reliable. When connecting the coaxial feed line between the high frequency head and the receiver, be sure to interpose the jack of the end tail of the coaxial feed between the metal shielding network of the coaxial feeder and the metal coating plastic paper layer, and then bind to the joint with the copper wire. Bundle.
3. The starring step first corrects the relevant data and information correctly. After the connection is completed, after the check is correct, turn on the power and call the main menu with the remote control. The main menu includes multiple content. Select the "Add Program" submenu in this menu, which is changed to 12537MHz (ie, 12.537 GHz, the following) in this menu, and the symbol rate is modified to 41248, the intrinsic frequency is modified to 11300MHz (must be consistent with the high frequency head ), The polarization mode is modified to be vertical, and the nature of the received signal is modified to "free". At this point, the relevant data and information input work ends. It should be noted that if the signal of the received beam is weaker, the stroned beam is stronger than the signal is used as the boot signal. The signal is a free nature that has no effect on the look.
Second, it is determined to determine the direction of the south, calculate the azimuth, elevation angle of the antenna, the polarization angle (commonly known as "three corners"). In my country, most of the region, most of the time, the north direction of the local time (ie, when the place) is determined on the surface of the sun rays. However, it should be known that 12 noon referred to here, can only be "place" at noon 12. Not seeing "Beijing time" noon 12 noon.
When Beijing time is actually a place in East 1200, it is the time of 120 ° in the sun. my country's things across 5 time zones, so the time of sunlight direct every place is certainly impossible to be Beijing time at 12 o'clock. Some of Shandong Zibo as an example. Since the Earth is rotated at 15 ° per hour (ie, a rotation of 1 degree required for 4 minutes), the time in which the sun light directs this place is at 12 o'clock in Beijing time + (120 degrees - 118.02 degrees) × 4 minutes / degrees, about 12:08. Similarly, the 1250 Daqing Sun Light direct this place is 11:40 am Beijing time, and Sichuan Ganzi is 13:20 pm. However, this method is used to determine where the south direction is also inconvenient. For example, my country's summer sunset sun Direct Northern Return line, place in the place of the North Return line, 12 hours in noon, the projection of the sun rays on the ground plane is only a point, so it is impossible to determine the origin and north. It is conveniently located in Wenchuan near the north latitude of 32 °. At this time, the projection of the sun rays is also very short, and it is difficult to determine the direction. In this case, you may wish to measure other times (such as 9 o'clock in the morning, 10 o'clock, 3 o'clock in the afternoon, 4 o'clock) the projection on the ground plane, and then calculate the sun azimuth at this time And marked the right direction.
The calculation formula of the sun azimuth angle is as follows:
SinαS = sinφ × SIN × 25 Cosφ × COSσ × COSΩ (1)
SINγS = CoSδ × SinΩ / COSαS (2)
Be
Among them, αs is the solar height angle, which is the local geographic latitude angle; δ is the sun's narrow angle: ω is the angle of the sun. Its definition is from noon, the clockwise direction is positive, counterclockwise, the value is the number of hours × 15 × 15; γS is the azimuth of the sun (ie, the ground is on the ground and the sun " The angle between the projections on the plane).
It is still a case in Shandong Zibo. Ask the sun azimuth at 10 o'clock on December 15th.
It is known that the geographic latitude angle φ of this place is 36.9 °; as can be known according to the time angle, the time angle ∞ is - (12-l0) × 15 °, equal to -30 °; the table can be seen, the sun The weft angle δ is -23.2 ° (see Schedule). The above data is subjected to equation (1), and ΔS = 2360 is obtained. ΔS = 23.6 °, δ = -23.2 °, ω = -30. Into the formula (2), γS = -30.1 °. Therefore, the solar ray indicated at this time is rotated at 10.1 ° clockwise on the ground plane, which is the local north direction. Similarly, Beijing on July 7th, the sun azimuth is 79.81 °, and Shenyang is 70.63 ° at 4 o'clock in the afternoon of September 18.
Note that the normal and negative angles in the middle of the calculation process can be interchanged, but the positive weight of both must be consistent.
Antenna azimuth, elevation angle, polarization angle can be obtained according to the following three formulas:
Among them, A is azimuth; B is an elevation angle; C is a polarized angle; φ is a local geographic heel - satellite longitude; Q is a local geographic latitude angle.
After calculation, Shandong Zibo received a square angle of 138 ° E Asia Pacific satellite, elevation angle, polarized angle of -31.4 °, 42.5 ° and -24.73 °. Of course, the above triangle is also completely found.
Due to the azimuth, elevation angle, the polarization angle corresponds to the horizontal calculation of somewhere on the earth, so the determination of the horizontal surface when the star is very important. The specific determination method is hereby not described herein.
Next, the azimuth of the antenna is first determined in accordance with the calculation results on the horizontal plane, and then the anode angle is slowly up-regulated while starting slowly from the lowest position, while observing the signal strength indicator strip and signal quality indicator on the television screen. The change.
When the elevation angle is large enough, the signal strength indicator on the TV screen reaches 80%, and the signal quality indication is 3% ~ 4%. It shows that the antenna is almost aligned with satellite. At this time, it should further slow down the anchor angle of the antenna. speed. When the above two indication strips began by yellow, it means that the antenna is basically aligned with satellite. After that, the triangle is repeatedly adjusted (the C-band antenna also adjusts the distance from the bottom of the antenna), until the signal strength, the mass is maximum. After adjustment, do a tag in the relevant part of the antenna so that you will find this star again. Finally, press the remote control key, the machine starts to automatically search, and the program on all Great Wall platforms is automatically downloaded. Pay attention to the star, the antenna must not have a metal network, a cement wall such as a metal mesh. Conditions can also install the feedback antenna to receive C-band's programs (such as C-band programs on Zhongxing 6b and C-band program on the Asian 3S. This second star C-band program, strong electric wave power, wide coverage, content Colorful, very valued), the propagation of this band signal is less affected by the rainfall. The communication of the KU band signal is determined by its own properties, and the influence of rainfall is large, sometimes even interrupted.
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