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make sure that the location is suitable. The proper direction may be initially
determined by making a comparison with other antennas. There should be no
objects directly in front of the antenna, for these may block the signal from
reaching the bowl! Once you select an optimal location for the antenna, fix and
adjust it initially, and then proceed to a precise adjustment. Each antenna is
fitted with regulating screws that make it possible to correct its vertical and
horizontal placement.
Adjusting is somewhat more difficult in the case of digital tuners. You cannot perform
adjustments on the basis of the image, because this appears with a certain delay. What is more,
the indicators available in the settings menu also act with a delay, and therefore adjustment
may take considerable time and be very imprecise. An antenna signal meter will be
indispensable for setting up the antenna. The meter must be connected to the antenna cable
between the converter and the receiver. This will confirm the presence of a voltage that
switches the converter from the tuner and show the signal strength for individual satellites. We
strongly recommend hiring a professional technician!
8. Connecting an antenna system with a positioner
USALS type positioners manufactured by Stab will guarantee the correct operation of your
Ferguson receiver. In order to connect an antenna system to a USALS positioner, you should
connect the positioner out to the LNB IN of the Ferguson receiver. The role of the positioner
installed between the mast and the antenna is to turn the bowl in such a way as to ensure that
it is directed to various satellite positions. The positioner is built in such a way that its axis of
revolution is parallel to the direction towards the North Star. For this reason, its mounting is
frequently termed the Polar mount. In consequence, when the satellite changes position, it is
not necessary to adjust the azimuth and elevation independently. The antenna revolves only in
one axis. Using the introduced scale, the motor inclines in such a way as to ensure the
appropriate placement of the axis of revolution. The angle of inclination corresponds to the
latitude of the location where the antenna is installed. As in the case of a fixed antenna, the
angle of elevation of the bowl must first be set. For this purpose, use is made of a satellite
located as close as possible to the south of your location. Ideally, the position of the satellite
should not differ from that of the said direction by more than 5°. In other words, you should use
the satellite position closest to the longitude of the point of installation. For example, if your
longitude is 73° W, you should search for a satellite located at a position between 68° and 78°
W.
automatically, provided that you have introduced their satellite position values correctly.
Without the USALS function, programming of the system is much more difficult. To this end you
should use the DiSEqC 1.2 function, which turns the antenna to the selected satellite in a nearly
identical manner. Since, however, it does not take into consideration the local geographical
coordinates, the movement is effected on the basis of the prime meridian and the equator.
Therefore it is necessary to introduce corrections separately for each satellite. Due to these
difficulties, manufacturers of DiSEqC 1.2 positioners frequently provide useful software on their
websites, using which you can easily calculate the location of the satellite.
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The USALS function considerably simplifies configuration of the
antenna. The Ferguson receiver requires that you enter the
geographical coordinates of the antenna in order to automatically
calculate the angle of revolution of the motor for individual
satellites. The receiver activates the positioner automatically and
turns the antenna to the selected satellite. When a signal is locked
on, you should precisely adjust the antenna's elevation and azimuth
settings in order to optimise signal reception. When correcting the
azimuth, the entire antenna assembly and positioner revolve with
respect to the mast. If initially the antenna was not directed
precisely south, you can correct this now. When you have finished
with the first satellite, all other satellites will be remembered
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