Promax HD Ranger Lite, Руководство пользователя

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July 2015
15
3
ANNEX 2 HOW TO POINT A DISH ANTENNA
A2.1
INSTALLING A SATELLITE DISH USING
HD
RANGER
Lite
A2.1.1
A bit of history
That's it, a bit of history. First artificial satellite "Sputnik I" was launched 4th of
July of 1957 by former Soviet Union. It was about the size of a basketball with a
weight below 100 Kgrs but went down in history as the start point for the space
age. For three weeks it was transmitting radio signals to the excited scientist on
the ground that were gathering fundamental data for the launches to come.
Figure A2.1.
The first telecommunications satellite was Telstar I launched in 1962. Some
people refers to Echo I as the World's first in 1960 but it was a passive signal
reflector as opposite to Telstar that carried electronics on board like today's
satellites. It was also the first to use the modern transponder concept where the
satellite "transposes" the up-link frequency (6,390 GHz in Telstar) to another
down-link frequency (4,170 GHz in this case). Telstar I trans-mitter power was 3
Watts and the antenna was omnidirectional.
Figure A2.2.