Sea Tel COASTAL 18, Инструкция по установке и эксплуатации

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Basic System Information Coastal 18 Ku-Band TVRO
3-2
Figure 3-1 Satellite Signal Polarization
where the boat can travel where the signal level is expected to be strong enough to continue providing
uninterrupted reception. When travelling outside this minimum signal coverage area, it is normal for the
system to experience an interruption in its ability to provide the desired satellite services until entering (or
re-entering) an area of adequate signal level (refer to the satellite footprint information in the Drawings
section of this manual).
3.1.5. Satellite Footprints
The focused beam(s) from the satellites are normally aimed at the major landmasses where there are
large population centers. Footprint charts graphically display the signal level expected to be received in
different geographic locations within the area of coverage. The signal will always be strongest in the
center of the coverage area and weaker out toward the outer edges of the pattern. The coverage areas
are intended to be a guide to reception, however, the actual coverage area and signal level may vary.
Also the signal strength is affected by weather.
3.1.6. Satellite Footprint Charts
A Satellite Footprint Chart is a drawing of signal level in a geographic region. You can refer to satellite
footprint charts (coverage maps) in World Satellite Almanacs or on the Internet (
www.SatCoDX.com or
www.Lyngsat.com ). Many satellites have their own web sites to provide programming and footprint
information. To use these footprint charts you will need to know the minimum EIRP signal level required
for your antenna (refer to the Specifications – Antenna section of this manual).
Contact your dealer for a footprint chart(s) of the satellite(s) you will be using with your model antenna.
These footprint charts show the locations where signal level is expected to be adequate for TV reception
with your model antenna.
Please note that while the coverage area information is believed to be correct, Sea Tel has no
control over actual satellite operation, footprint coverage, or programming. The coverage maps
are intended as a guide to reception and the actual coverage area and signal strength may vary.
Also, signal strength and reception within the footprint may be affected by weather.
3.1.7. Satellite polarization
Satellites may transmit their signals in one of two different polarization modes. Your antenna is designed
to operate with
linear OR circular polarized satellite transmissions, but you must have the appropriate
LNB installed for the satellite that you want to receive.
Circular polarized satellite transmissions
do not require polarization adjustment to
optimize the reception.
Linear polarized
satellite transmissions require periodic
adjustment of “polarization” to optimize the
alignment of the LNB to the angle of the
signal from the satellite.
Your antenna is designed to automatically
adjust the polarization, even when you
have a circular LNB installed. When you
are operating with
linear polarized satellite
transmissions the auto-polarization is
periodically adjusting the
linear LNB “polarization” to optimize the alignment of the LNB to match the
angle of the signal from the satellite.
When you are on the same longitude as the satellite, its’ horizontal and vertical signals will be purely
aligned to your horizon. When the satellite is east or west of your longitude, the satellite signals will
appear to be rotated clockwise or counter-clockwise from pure horizontal and vertical. Both horizontal
and vertical signals from a satellite will appear to be rotated the same amount and are always
perpendicular to each other. The amount of rotation is dependent on how far east or west the satellite is