Sea Tel COASTAL 18, Инструкция по установке и эксплуатации

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Operation Coastal 18 Ku-Band TVRO
2-4
Figure 2-3 LNB rotation during polarization adjustment
Figure 2-4 LNB rotation during polarization adjustment
2.4. Linear Polarization Adjustment
Polarization is adjusted for a desired
satellite when the system is initially
installed. Subsequently it needs only to
be adjusted when changing from one
satellite to another, or when the boat has
traveled a significant geographic
distance. It should NOT need to be re-
adjusted if the boat stays in the same
location and is operating on the same
satellite.
Polarization of your Series 98SL antenna
must be accomplished manually. Each
time you need to adjust the polarization
you will have to take the radome top off,
loosen the LNB mounting set screws and
rotate the LNB. When you have
optimized the polarity, tighten the set
screws and put the radome top back on.
The adjacent figure shows the rotation of
the LNB assembly mounted on the back
side of the dish as it would be seen if observed while polarization is being adjusted. As the polarization is
mis-adjusted, the signal level will degrade. If it is mis-adjusted far enough, the signal will be completely lost.
Note: The polarization entry from the Antenna Control Panel will NOT electrically rotate your LNB. Each
momentary keypress of the
▲
(POL UP), or
▼
(POL DOWN), will increment/decrement the displayed value
but will NOT rotate the LNB.
The antenna reports that it is tracking a good signal by displaying a steady (ON) TRACKING LED. If you
determine that the satellite signal is not the desired satellite, press the NEXT key to search for the NEXT
satellite signal. Continue repeating this procedure until the correct satellite is found. Once the correct
satellite has been found, allow the antenna to track for 4-6 minutes to update the satellite position
information.
2.4.1. Optimizing the polarization while on the desired satellite
This adjustment should be done while the boat is at the pier and antenna is tracking the desired satellite.
When the boat is travelling to a different
geographic area the polarization may need
to be re-optimized if performance appears
to be degrading.
Select the “Signal Strength” display of the
satellite receiver (refer to the satellite
receiver manual). While monitoring the
receivers’ signal strength, adjust
polarization up or down in one (or two)
degree increments, then observe the
receivers’ signal strength for 10-15
seconds to evaluate the change. If an
improvement is noted, continue small
adjustments in the same direction until the
highest signal strength is obtained. If the
adjustment causes a decrease, adjust
polarization in the opposite direction to
increase the signal strength. When the polarization of the antenna is optimum, tighten the set screws and