Hughes HughesNet Ka-band, Руководство по указанию

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Chapter 2 • Pointing the antenna
1037663-0001 Revision A
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Attaching Squinter types B and C
a. To attach squinter types B and C, place the squinter on the
feed horn, making sure that the four keys around the
perimeter of the feed horn fit inside the corresponding
grooves on the inside edge of the squinter, as shown in
Figure 11.
b. Once the squinter is attached to the feed horn, loosen the
two-piece collar that connects the feed horn to the radio
assembly and plumb the elevation plane by rotating the
feed horn until the bubble in the squinter level is centered;
then re-tighten the collar around the feed horn stem. This is
the first azimuth position.
c. Wait for the SQF reading to settle on a value. (The time
required is a function of whether you are using the short
filter or the long filter.) When the reading has settled, note
the SQF value on the display.
Figure 11: Attaching squinter types B and C
Note: When reconnecting the collar, be sure that the point
where the two halves of the collar meet lines up with the seam
on top of the polarizer waveguide.
Note: If using the short filter, you must wait at least 3
seconds at each dither point. If you do not wait before
recording the reading, the pointing signal may not have
reached its steady-state value, and will cause a pointing
error. If you use the long time constant filter, you should
wait at least 15 seconds to take a reading.