Satellite Dishes And Lnbs - ViewSat VS9000HD Troubleshooting Manual

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(12) SATELLITE DISHES AND LNBs:

ere are many types of Satellites Dishes but not that many for HD Receivers. As far as LNBs I have found
most work with HD Receivers.
A satellite dish is a type of parabolic antenna designed with the specific purpose of transmitting signals to
and from a destination, whether it be a satellite or an aerial eg: WIFI ANTENNA. A satellite dish is a
particular type of microwave antenna. Satellite dishes come in varying sizes and designs, and are most
commonly used to receive satellite television. Many of the offset type of satellite dishes are sections of a
larger parabolic dish.
e parabolic shape of a dish reflects the signal to the dish's focal point. Mounted on brackets at the dish's
focal point is a device called a feedhorn. is feedhorn is essentially the front-end of a waveguide that
gathers the signals at or near the focal point and 'conducts' them to a low-noise block downconverter or
LNB. e LNB converts the signals from electromagnetic or radio waves to electrical signals and shifts the
signals from the downlinked C-band and/or Ku-band to the L-band range. Direct broadcast satellite dishes
use an LNBF, which integrates the feedhorn with the LNB. (A new form of omnidirectional satellite antenna,
which does not use a directed parabolic dish and can be used on a mobile platform such as a vehicle was
announced by the University of Waterloo).
Modern dishes intended for home television use are generally 43 cm (18 in) to 80 cm (31 in) in diameter, and
are fixed in one position, for Ku-band reception from one orbital position. Prior to the existence of direct
broadcast satellite services, home users would generally have a Motorized C-band satellite dish of up to 3
meters in diameter for reception of channels from different satellites. Overly small dishes can still cause
problems, however, including rain fade and interference from adjacent satellites.
Motorized satellite dishes are still popular with enthusiasts. ere are three competing standards, which
often are all supported by a set-top box, DiSEqC, USALS, and 36v positioners. ey can only supply one
receiver.
ree Different Satellites that are used with HD receivers.
from the left: Dish 1000.2 3 LNBs Center: Dish Plus 30" 2 LNBs Right: Dish 500 Pro 2 LNBs
NOTE: Direct TV and other HD Satellites Providers not shown.
Problem with Satellites are with Connections, Cables, LNBs and dialing the Dish to target.
VIEWSAT 9000HD User Troubleshooting Guide & Manual. April /2008