What you need to know: A Quick Overview
1) Azimuth refers to the horizontal measurement of a
direction. In terms of your satellite dish, it tells you how far left or right
your dish should point.
2) Your elevation gives your satellite dish its heading, or
how far above the horizon it needs to point (up and down).
3) Polarization also known as "skew", refers to
the adjustment needed for the curvature of the Earth. This rotational
adjustment compensates for the Earth’s curvature between the dish and the beam
of the satellite.
With your azimuth and elevation numbers in hand, get a
compass. Standing close to your
satellite dish, rotate your compass until the needle points North, or
zero degrees. Starting from this point, locate the azimuth number on the
compass and turn to face that point without moving the compass itself. East is
90 degrees, South is 180 degrees and West is 270 degrees. If your azimuth
number is 240 for example, you would face a direction between South and West on
your compass.
You can use this tool to determine where to point your
dish>> SATELLITE FINDER
http://www.dishpointer.com/
The above link will take you to a
site where you enter the satellite (Galaxy 19, 97ow) and then your location. A
satellite picture of your location will appear (takes a little time) with a
pointer symbol and a line, move this pointer to the exact (as close as you can
come) place you are installing your dish and use the landmarks the line passes
through to determine where to point your dish.
If you do not have internet access at your location we
suggest you use this link >> http://www.dishpointer.com << at a location (library, etc)
that does have internet access and print out the map so you have a reference
sheet as to where your dish is to be pointed.
Now that you’ve found your direction (left/right), estimate
the angle of elevation (up/down). With the ground representing zero, calculate
the distance going upwards using the elevation number. Straight up would be 90
degrees, so if your elevation number was 45, your elevation would be halfway
between the ground and looking straight up into the sky.
It is important to note, your dish antenna must be installed
correctly before you can attempt to align your dish to the correct satellite to
receive satellite transmissions.
Pointing your satellite dish antenna to the correct spot in
the sky to receive satellite signals is a task which can be accomplished by
anyone with the knowledge and desire to do so. However, depending on your
particular setup, you may need some additional help.
Aligning a satellite antenna (dish) to a broadcast satellite
for the purpose of receiving a signal.
We live in a three dimensional world. You can think of the
three dimensions as height, width and depth.
For purposes of aligning your dish antenna, we will call
height, elevation and we will call width, azimuth. Azimuth is just a fancy word
for direction. The depth would be the distance from your dish to the satellite
or about 23,748 miles. To receive your satellite TV signal from the correct
satellite you must point your dish to a specific spot in the sky which will
give you the best possible signal strength. This spot is the location of your
satellite in space. The question is, how do you determine exactly where to
point your dish?
1. Elevation
- Angle between the Earth and the satellite, above the horizon. This is also
referred to as the up or down movement (position) of the satellite antenna
(dish). Elevation is measured in degrees. Elevation is the upward tilt of a
satellite antenna, measured in degrees, required to aim the antenna at the
satellite. Think of elevation as follows: If you stand straight up and look out
to where the land meets the sky (horizon) hold your arm straight out and point
to the horizon, this is zero degrees elevation. Start moving your arm up slowly
and point to the sky. You are now elevating up in degrees. When you get to
where your arm is straight up pointing to the sky right above your head, this
is 90 degrees. What you'll be looking for when pointing your dish is an angle
somewhere in between zero and 90, most likely 30 (northern states) to 55
(southern states).
Elevation
2. Azimuth
- Compass direction the antenna is pointed towards, relative to a magnetic
north. This is also referred to as the left or right movement (position) of the
satellite antenna. The angle of rotation (horizontal) that a dish antenna must
be rotated through to point to a specific satellite in orbit. The angle is a
north to south line through the antenna’s location, measured in degrees
clockwise.
Azimuth
3. Polarization
- Correction between where the antenna is relative to the curvature of the
Earth and the satellite’s signal beam. The satellite signal is either
Horizontal or Vertical polarized, but due to the longitude of the antenna
location, the antenna’s feed horn must be rotated to correctly match the beam's
polarization.
Determining the Elevation and Azimuth
The satellite appears to be fixed in space approximately
23,748 miles above the equator. In reality, the satellites travel from west to
east, but to us on Earth they appear stationary because they match the exact
speed of the Earth's rotation. (This is a geostationary orbit.) If you stand up
now, turn towards the southern sky, and tilt your head up to the heavens, you'll
be looking in the general direction of the DBS satellites.
To aim your satellite dish antenna at the satellite, you
need to know your azimuth and elevation coordinates. Azimuth is defined as the
horizontal direction expressed as the angular distance between the direction of
your dish and the direction of the DBS satellites. More simply, azimuth relates
to the left-to-right positioning of your dish. Elevation is the angular
distance of the satellite above the horizon in relation to your dish. In other words,
elevation concerns the up-and-down positioning of your dish.Further
explanation: A geo-stationary satellite in orbit around the Earth remains above
the same location on Earth since it's orbit is in synch with the Earth's
rotation. The satellite transmits it's signal to Earth after receiving it from
an Earth ground station. Your dish antenna captures the signal and focuses it
on the LNB which feeds it down a cable to your receiver which decodes it and
sends it to your television. The dish antenna has to be aligned properly so
that it can capture the signal. It has to be pointed towards the signal and
fine tuned for maximum signal strength.
For each location on the Earth's surface which can capture a
particular satellite signal, you have to align the dish at different angles to
receive the best signal. Everyone in the Northern hemisphere of the Earth
(includes the United States) has to point their dish towards the southern sky
since the satellite you require is positioned over the equator. A dish in North
Dakota has to be pointed lower than a dish in Texas. A dish in Florida has to
be pointed differently than a dish in California.
You can use this tool to determine where to point your
dish>> SATELLITE FINDER
Now that you have your azimuth and elevation coordinates,
what do you do with them?
Set up your dish antenna to ensure an unobstructed line of
sight to the satellites. To receive satellite broadcast signals, your dish
needs to be positioned correctly. Mount your dish so that the base fits flush
with the mounting surface (level if mounted on a flat beam or roof, or on an
angle to match the pitch of your roofline). When you have securely mounted your
dish, adjust it so the dish mast is plumb, that is, exactly perpendicular to
level — this is best achieved using a carpenter's bubble level. With your dish
now mounted and properly set, you are ready to aim your dish toward the proper
satellites.
To set the dish to point up to the satellite, you'll first
need to set the elevation. Then you'll point the dish in the proper
left-to-right position to set the azimuth.
For anyone in the U.S., begin by pointing your dish to the
South. If you do not know where South is you can use a general purpose compass
to determine North and South.
Setting the Elevation (UP), (DOWN)
You can set the proper elevation after the dish is securely
mounted. First, loosen the nuts securing the two elevation bolts so that the
dish easily moves up and down. Line up the elevation indicator with the tick
mark corresponding to your elevation number. Then tighten the bolts.
Setting the Azimuth (LEFT), (RIGHT)
Loosen the azimuth nuts on the LNB arm enough that the dish
can be turned smoothly with little pressure. Set the azimuth by moving the dish
left and right. Point the dish in the general direction of the satellite, in
the southern sky. By using a compass you can better pinpoint the direction with
your azimuth number to correspond with the degrees on your compass.
Acquiring the Signal
Now your dish will be in position to lock in on the
satellite signal. You'll need to
1) have your satellite receiver connected to your
television, with both turned on, and
2) have your antenna to receiver cables connected, and
3) be viewing your Setup Antenna/Signal Strength display
from your on-screen menu to measure the signal strength accurately.
Ask someone to watch the Signal Strength screen for
indications you are receiving the signal. Stand behind the dish, and holding
its outer edges, slowly turn it a little to the right to adjust the azimuth.
Pause a few seconds, giving the receiver enough time to lock in on the
satellite signal. Continue turning the dish in this way until you have acquired
the signal or until you have rotated the dish approximately 15 degrees from the
starting point.
If you haven't detected a signal yet, return to the starting
point and move the dish to the left again. If you don't acquire the signal
after rotating the dish approximately 15 degrees to either side of the
calculated azimuth angle, loosen the elevation bolts and tilt the dish upward
so the elevation indicator moves halfway from the current tick mark to the next
mark. Then tighten the elevation bolts. Repeat the azimuth adjustments again to
lock in on the signal.If the signal still eludes you, check:
• that
nothing — a tree, for example — obstructs the signal
• that the
cables are connected properly to the receiver
• that you
have the correct azimuth and elevation coordinates
Fine Tuning
When you have received the satellite signal, it is important
to fine-tune the dish pointing to make sure you have the maximum possible
signal strength. Maximizing the signal is important in that it reduces
"rain fade" during inclement weather. Loosen the elevation bolts,
then gently continue turning the dish a little in the same direction you were
turning it when you began to receive the satellite signal. Pause for a few
seconds each time after moving the dish. Turn the dish in this way until the
signal strength reaches its highest reading and then begins to fall. Then
slowly turn the dish the opposite way until you again receive the highest
reading on the Signal Strength screen.
Important: The Signal Strength reading does not need to be
"100." Lock in on the highest possible signal which is usually 70 to
85.
Tighten the azimuth bolts. Loosen the elevation bolts.
Slowly tilt the dish up and down to improve the Signal Strength reading. When
you are satisfied that you have the strongest signal, tighten the elevation
bolts.
Another website to look at for azimuth & elevation
calculation: http://www.satcruiser.com/azel.htm
You may need to adjust your azimuth angle to account for
magnetic declination.
References:
Links: