Told last time, how to work with multifeed to catch more satellites. On any spacecraft hits the LNB has a fixed position on the guide fixture. It costs money, the farther the satellite deviates from the normal to the plate, the lower the efficiency of the system - decreases energy reception area. If the satellite dish to turn sideways to the spacecraft, the reception will be impossible. Let us discuss these factors, talk, how it's performed installing a satellite dish yourself.
What's wrong in multifeed satellite antenna
Adjust the satellite dish to the satellite is not difficult, complicated, if the satellite is not the only one. In previous reviews have addressed the issue multifeed mounting. It showed that the closer a satellite is located to the south, the more one can see in the sky, elevation more. If the antenna is pointing straight at the equator, multifeed looks like a small semi-circle with the "horns" up. The bend in a length of 30 cm from the center of 3 cm for a radius of 60 cm dish for Novosibirsk latitude (55 degrees North). What if the antenna aperture is not looking just to the south. In the latter case, a little crank around the axis need multifeed.
The stronger the rejected plate from the direction of the south, the more the need to rotate around the axis of multifeed.
When were calculated in the last time, you said that in the south of the satellites hang high above the horizon down closer to the ground. The orbit is circular, watching angle, we see an ellipse. It decided to take the three points - in the center and two at the horizon - on points to build a circle. Accordingly perform multifeed having calculated distances and angles. On the length of the aperture plate a big difference between a circle and an ellipse is not noticeable, large errors will not work.
A similar case, when the center of the plate deviates from the south. It relies multifeed tilted slightly to the side, which has moved the antenna field of view. It turns out that the party multifeed south will be slightly raised. How many, a difficult question, see the calculation of the survey "How to set up a satellite dish on their own" for more information. The review provides an example, provides links to useful sites. For these any more precise information will calculate how to position the plate. As a consolation, we say that the transponders for end users (DTH) are powerful enough signal sometimes caught typical metal lid bin is already discussed in the reviews.
What's wrong with the method mulitifida? Let's say, we live in the forest, to do nothing, the family entertainment needs. We believe that the only NTV not satisfied. In order not to miss, catch Internet, sports channel, where children are taught. Consider what to do if the satellites in different parts of the horizon. Hang on a flotilla converters multifeed? Here we are faced with the complexity of: signal strength. Satellite drops with a deviation from the normal to the plate due to the decrease of the effective area of the antenna, in addition overlap the converter body portion of the signal. The result is not too good, expensive event.
It is useful to think about the use of the positioner. The device costs 4000 rubles, and lets you modify as necessary the angle of the antenna to catch the other satellites. It is necessary to adjust the angle of elevation and azimuth. Positioners provide accuracy of 0.1 degrees, which is enough to solve pressing problems.
Rotator satellite antenna
So, seeing the difficulties of providers, lack of coordination, the unwillingness to make concessions and to introduce standard solutions, manufacturers released servomotors, the ability to rotate the antenna in two planes: azimuth and place. Inside the worm gear is used, the device is controlled by the protocol Diseko (e.g., DiSEqC 1.2).
The differences are unimportant, as long as the receiver is driven by motor spravno. With voltage signals 13/18 B and 22 kHz tone sending channel tuning occurs antenna position. The operation is transparent to the user, if the receiver is compatible with the desired protocol. Then go variation.
If you take the engine Strong SRT DM2100, in memory of the device recorded 60 positions. The rotation angle in azimuth of the engine is 160 degrees, which will lead receiving-orbit within view of the sky. It is advisable to direct the center span due south. Say more, in our latitudes characteristics even superfluous, for the tropics need these extraordinary opportunities. Think point at a decent distance from the equator, so the arc over the horizon comes much earlier than the limit has been reached. Check out the map ( http://www.tricolor78.ru/karta.html):
- Hotbird satellite at 13 degrees East is visible from Novosibirsk at an angle of azimuth 253 (with a small) degree.
- Satellite JS SAT 2A - angle 105 (with a small) degrees azimuth.
The practical limits of visibility, we estimate the spread. Is 253 - 105 = 148 degrees. Our antenna will provide 160! Hence, the device is suitable for Novosibirsk and north latitudes, where the requirements below. The spread of elevations is 25 - 75 degrees. Device feature the ability to eliminate the backlash adjusting screws, in two planes. If the antenna is shattered by the wind, with simple operations, normalize reception. The worm gear being transferred from the first end position to the opposite for 50 seconds. As long as the antenna is moving, patiently waiting.
The device weighs 12 kg, the front panel easy to understand (pictured in English) says that where to connect, how to use the device. Indicated by the arrow East-West to the engine I know which way to develop the team. Specified key assignments:
- The first antenna for manual rotation. Near it is written that by pressing and holding times, we get a smooth shift to the holding period to the west. Press twice and hold, move the antenna to the east. About the elevation does not say.
- To the right is a reset button. If the green light, the configuration is OK if red is not enough voltage.
Rotator satellite antenna
Two slots for f-connectors are marked: one for the converter (LNB), the second for the receiver. Possible difficulty. NTV broadcasts to circular polarization, and Europe tend to be linear. If you want to watch, either need to use two converters connected via Diseko switch or try a universal (hybrid). Know the ideal receiver do not have today. Converter, perfectly in receiving Ku, C will give failures and vice versa. Not able to combine equipment schemes of circular and linear polarization. Expected loss in signal level.
Coupled with the rotary device is logical to use exclusively hybrid converter. There is an additional catch: linear polarization angle of inclination varies. On NTV + is not expected inconsistencies, but Europeans zasboyat. Note rotator changes the elevation angle and azimuth, but can not tilt the converter appropriately. Due to the latter any further loss. By the slope of the horizon increases. Permissible figure out what angle your favorite programs, and to expose. For others have to put up with losses.
There are many sub-bands n-Noe number of types of polarization. It does not meet the requirements of the cosmopolitan. Restrictions are imposed on the dimensions of the antenna:
- The maximum diameter of 1.2 m reflects the wind load, which will withstand a worm drive.
- The maximum weight of 14 kg in addition characterizes the wind loading on a break, and others.
To manually set up a satellite dish, you need to choose the right size and type of converter plates. satellite transponders for DTH powerful enough, because losses do not make big adjustments. But with a single converter see any programs. With the setting will tinker, adjusting the angle of inclination preferably converter. If the drive of the crank, the backlash is eliminated instrument for 5 min. Note that when the number of satellites to three independent satellite antenna installation with a billion converters fly expensive. The rotary device costs less than 4000 rubles.
We hope that helped readers understand how to install a satellite dish, with or without motor. Both methods have their place. A satellite dish installation yourself sometimes useless. In NTV, for example, the device is attached. If you are trying for it to take the money, take the trouble to inform the provider. They will be deprived of a license or pay a fine, return the money.
Note! In 2017 the rules are different. Read more on the website Tricolor tricolor.tv/help/connect/.