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Satellite Earth Station
The satellite dish antenna used to receive the ARCS signal. The dish
is aimed at AMC-8, the same satellite owned by SES-Americom and used
by ATT/Alascom. It sits in orbit at 139 degrees west. The dish can be
adjusted in three ways: it can move up/down, left/right, and it can
rotate clockwise/counterclockwise. Of course, the whole dish doesn’t
rotate, just the center part called the feed horn. Not all dishes are
equal; some have their feed horn mounted at the back of the dish, and
use an extra reflector to capture and focus the satellite’s microwave
energy into the feed horn. Others have their feed horns mounted on arms
in front of the dish where the microwave energy is reflected to a single
point of focus. In either case, the feed horn must be free of debri
and moisture to effectively conduct the microwave energy into the LNB,
or Low Noise Block converter.
The LNB is an electronic device that gets its electrical power from
the receiver via the coaxial cable which connects the two devices. It
operates at a very low voltage and its circuits are completely sealed
from the elements except for the connector where the coaxial cable attaches.
As long as this connection is sealed properly, the LNB will operate
normally, even in rain, wind and snow.
The condition of the dish’s construction is vital to the overall
performance of the signal. Warps, dents, bent arms, or missing pieces
will weaken the signal, as will any obstacles between the dish and the
satellite at which it is aimed. The dish was originally mounted on a
level surface; however, due to shifting ground the dish may experience
slight movements, especially through the seasons if frost heaving is
occurring. With the right expertise and tools, it is possible to re-aim
the dish, but it is not a chore to enter into lightly.
All of the factors mentioned here can have an impact on the dish’s
ability to deliver strong clean signal to the receiver; any combination
problems in these areas can cause intermittent outages which will show
up as frequent pixelizing (green squares and frozen screen) and even
failure of the receive chain. If you notice problems with your dish,
call 888-840-0013.
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