Hughes HughesNet Ka-band, Руководство по указанию

Страница: 30 / 44

Chapter 2 • Pointing the antenna
22
1037663-0001 Revision A
d. Remove the squinter from the feed horn, rotate it 180
degrees to the opposite azimuth position, and replace it on
the feed horn, again making sure that the four grooves fit
over the feed horn keys.
e. Wait for the SQF reading to settle on a value and check the
reading at this position.
f. Compare the two azimuth readings. They should be as
close as possible to within 5 SQF points. Continue to
adjust the azimuth and take pairs of readings until the two
azimuth numbers are within the tolerance level of 5 SQF
points.
g. Remove the squinter from the feed horn, rotate it 90
degrees to the first elevation position, and place it back on
the feed horn, again making sure that the four grooves fit
over the feed horn keys.
h. Wait for the SQF reading to settle on a value and note the
SQF value on the display.
i. Remove the squinter from the feed horn, rotate it 180
degrees to the opposite elevation position, and replace it on
the feed horn, again making sure that the four grooves fit
over the feed horn keys.
j. Wait for the SQF reading to settle on a value and check the
reading at this position.
k. Continue to adjust the elevation and take pairs of readings
until the two elevation values are within the tolerance level
of 5 SQF points.
l. When the pair of elevation readings is within 5 SQF points,
check the azimuth readings again to ensure that they were
not altered during elevation adjustment. Make any
adjustments as necessary using the fine az/el tool.
m.Lock down the azimuth.
n. Measure the top and bottom elevation readings again to
make sure that they have not been altered during azimuth
lockdown.
Note: The tolerance level after antenna lockdown is 15
SQF points. However, the position of the antenna will shift
during lockdown, so you will need to get within 5 points at
this time to compensate.
Note: Because slight movement of the antenna occurs
during lockdown, always measure the elevation readings
again after locking down the azimuth. When this second
pair of elevation readings matches, you can lock down the
elevation.