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 debris 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 pixelating (green
squares and frozen screen) and even failure of the receive chain. If you notice
problems with your dish, call 888-840-0013.