On 10/18/1999 at 06:43 AM, Randy Walters <RandyWal@ix.netcom.com> wrote:
> About this line of sight thing, i have an interesting story. My next
> door neighbor works for Direct TV here in El Segundo, Calif. She
> gets DSS for free, and had her dish installed by Direct TV technicians.
> When they were mounting the dish to her roof, they had it pointing
> directly at my 2nd floor bedroom wall as my building is blocking her
> line-of-sight to the satellite. On top of that, there's a 3-story apt
> building on the other side of me, further blocking her line-of-sight.
> Her dish angle is very shallow, maybe 20 degrees from horizontal.
It's real simple. The dish may only be aimed at 20 deg to horizontal, but the
signal's coming in from much steeper than that. If you've ever looked closely at
the dish you'll notice 2 things: 1) the disk is actually oval (long side
vertical) and 2) the receiver is not mounted dead center of the dish, but offset
below that. The dish is designed to reflect the signal coming from the satellte
toward the receiver not like the radio antennas you see, or even the big C band
dishes, but more like a mirror catching the sun and angling it into someone's
eyes :^). I think this is so that snow et al does not build up on the dish so
much since it's sitting at such a sharp angle to the ground.
Just a data point The angle for my dish setup it something like 45 deg (where
the satellite it above the horizon at my position). But there's no way my dish
points up at 45 deg. It points more like 15-20 deg.
Mike
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