Promax HD Ranger +, Руководство пользователя

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16 December 2014
The antenna used to receive the test transmission from Telstar I was a huge horn
inside a bubble radome 48 metres high. Only four decades later we have broken
all records and we have high power DBS geostationary satellites carrying a lot of
digital transponders on board and we start to worry about space junk having
thousands of satellites in orbit, plenty of them beyond its useful life. Satellites
use highly efficient directional antennas and very high transmitters power, digital
transponders, meaning in plain words that we can receive hundreds of TV
channels with a small, fix, cheap, 60 cm dish.
Figure A2.3.
Modern broadcast satellites use geostationary orbits. This simply means that
they could be seen from the ground hunging in the sky at the same exact
position all the time and therefore receiving signals from them does not require
complex steering systems. A piece of cake.
All we need to do to receive their signals with the enormous amount of programs
they carry is to set up the satellite receiving antenna properly and to ensure that
the signals are received with the proper quality levels…and here is where the
HD RANGER +
comes into action.
A2.1.2
The basics
A professional installer will instantly tell us from the top of his head what to have
in the to-do-list if we want to install a satellite dish properly. Surely the list will
require us to select the proper mount kit and dish size from the numerous
options available in the market, pick a good location for the dish, free of
obstacles to the south (in the north hemisphere) or to the north (in the south
hemisphere), etc.
Other than the mechanical bits and pieces the dish is made of two clearly
differentiated parts, the reflector and the LNB.
The reflector is passive and simply reflects signals from the satellite in such a
way that the beam is collimated to the LNB's mounting point.