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Old May 13th 04, 12:17 AM
Uncle Peter
 
Posts: n/a
Default Parabolic dish gives weak performance increase

( Odd thing about this dish -- this one is a DishTV brand -- is that in
the
original design for satellite reception, the driven element [ the "can",

the
input to the LMB ] was located low on the dish. In other words, the focus
used in this design was off-center, about 30 degrees below the center axis

of
the dish. This would mean that aiming would be off-axis, too, yes? What is
the reasoning behind this design? )


1. Prevents the LNB converter from shadowing a major portion of the
dishes surface with loss of gain.

2. Since the angle of the received signal is offset by the same number
of degrees as the feedhorn offset, this results in a more vertically
plumb dish surface that more readily sheds snow and ice buildup.

Pete K1ZJH