Wednesday, January 20, 2016

How to Point a Satellite Dish

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

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 >>  << 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).
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.

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: 

You may need to adjust your azimuth angle to account for magnetic declination.



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