question about 10' C- band dish [Archive]

Crow 492

07-28-2005, 04:39 PM

Here is evrything that you will need here.

C-Band how to.

--------------------------------------------------------------------------------

I recently set up a C-Band system up from scratch, so I thought I would share how I did it.

First off, since you will be more than likely hooking this up to your fta reciever or dvb card, there are certain things that will have to be taken into consideration. For instance, dish size. When you are looking for a dish, generally bigger is always better, but since you will only be watching digital channels with an fta reciever, dish size is not nearly as critical. Generally a 6' C-Band dish will give you a 50% signal on a digital channel. I would be all for having a 16' Paraclipse dish sitting in my back yard, but the nasty divorce thing that would more than likely result from that would not be worth the while. Also pay attention to the type of lnb that is on the dish. Old dishes had what was called an LNA, it works rather well, but is incompatible with fta because it converts the signal to a 70 mhz frequency that an fta reciever cannot pick up. The desirable one is what is called an LNB. These are found on all newer dishes and work perfectly with fta. An easy way to identify what a dish has, is the mesh on it. If it has holes that are bigger than a pencil lead in the mesh(more on the mesh later), typically it will have an LNA. Also, a feedhorn that has C and Ku bands is a definate bonus.

The next thing you will want to look for is an analog reciever. You will want a reciever for two reasons. 1) It will make aiming and tweaking your dish MUCH easier and 2) You will use it for moving the dish and changing polarity on the feedhorn. Recievers are cheap these days and can be had for about $20 online. I wouldn't worry about its features too much, but I would reccommend getting a remote with it to make dish moving easier. Also, make sure it is new enough that it will work with an LNB.

As far as acquiring a dish, these are rather easy to find just by driving through the country. People literally give away dishes away these days. When you locate a prospective dish, be sure to give it a thorough inspection. Check for warpage with a tape measure, make sure all measurements across the width of the dish are exactly equal. Also check the mesh on the dish to make sure the holes on the mesh are small enough that you cannot get a pencil lead through the holes. This is important because if the holes are too big, it will not reflect Ku band signals very well. If all you want is C-band, this kind of dish would be fine, but if you want Ku and DBS sats, small mesh is much more desirable. Check the mounting hardware and the actuator motor for rust and other damage. The actuator motor is another highly important to watch for. There are two or three types of actuators. They all operate in basically the same way, but the sensors that give the reciever feedback come in a few different varietys. Older ones use a 10 turn potentiometer to show its position. Newer actuators use a hall effect sensor that use pulses to sense position. This needs to match your reciever to properly move the dish.

On to the hookup:
You will need to get a couple of bags of concrete and set your pole up. Make sure it is perfectly level and tall enough so the bottom of the dish doesnt hit the ground at extreme east or west. Once the concrete is dry, mount your dish and set up a reciever and tv next to the dish. There will be four wires coming from the actuator arm and three from the polarotor. The actuator arm should have two thicker wires to power the motor itself and two sensor wires to show its position. The polarity on the sensor wires is not important, but The motor itseff gets DC power, so if the dish moves the wrong way when you move it, switch the two thick wires. The polarotor is a small servo motor that will change polaritys on the feedhorn. It will have 3 wires on it, a black one for ground, a red for 5-6V+, and a white wire for reading its position, it will typically be hooked to a terminal called pulse on the reciever. The dishes pole mount should give you some indication of how to initially point it. It won't be exact but will get you close enough to start tuning it. Once that is done, use the reciever to point the dish as close to straight south as you can. Once you are there slowly move east and west to find a signal with your reciever. Usually channel 9 will be active on most sats. Once you get a signal try to fine tune your dish east and west for the best signal. Once it as good as it going to get, pull up and down on the dish and see if the signal improves any. If it does, adjust the elevation on the elevation nut on the back of the dish. Once you have a good lock on the sat, move your dish to one of the sats that are low on the horizon. Repeat the same process. If the elevation is way off, try moving the dish around a little bit on the pole and try again.

Once you get a decent amount of sats locked in on your reciever, go ahead and tighten all of your pole mounts down and set your dish limits in your reciever. You will want to set them about 5 seconds of travel past the east and westmost sat that you can track in the sky. Once complete, you can bring the tv and reciever back inside and set it up where you want it. You will need a length of seven conductor cable to control everything without seperate wires running across the yard. I would reccommend getting seven conductor thermostat cable from any big hardware store, its a little expensive but looks much better than 3 or 4 seperate cables running across the yard.

Tune in a sat on your analog reciever that lyngsat says also has digital feeds, and then unhook the coax to your analog reciever and plug it into your fta reciever. Go ahead and scan that sat and see what channels it finds, since most recievers cant change polarity on their own, you will have to scan again after changing polaritys on the reciever(moving channel up or down one). Once you get some channels on your fta reciever, fine tune the skew on your analog reciever for the best signal strength and watch tv.

How to install your Dish for FTA

- Free to Air Installation -

A satellite free to air installation can be accomplished by most people that have the patience to follow instructions and a moderate electronic knowledge. If this is not for you, it will be far easier for you to contact a local satellite installer in your area to assist you. This tutorial assumes you wish to receive multiple satellites using a dish mover or rotor. If you only wish to receive a single satellite, your task is much easier as you have but one satellite to locate and your dish will be fixed on the single location. For most broadcasts in the United States and Southern Canada, a dish size of 90cm - 1.2 Meters (30" - 48") is sufficient. Larger dish sizes may be required for more northern or out of footprint locations.

Definitions to Know

Elevation This is the angle between the broadcast satellite above the horizon and your physical location on Earth, where your receiving satellite dish will be. This is the up/down adjustment on the satellite dish. All commercial satellites in geo-stationary orbit are located 22 300 miles above the Earth. The curvature of the Earth means that the farther you advance East or West from the satellite orbital location, the more you will need to adjust your elevation. For example, if the satellite orbital location is located directly over the state of Texas, your elevation in New York will be lower than that of someone living in Texas.

Azimuth This is the compass direction to your satellites location. This is the left/right adjustment on the satellite dish. For example, to find a satellite located at 101 degrees longitude , your azimuth in Los Angeles, California will be 137 degrees. Also, as there is a difference between true and magnetic North, to find a satellite, you may also need to compensate or correct your values for magnetic deviation. (See below image) For Los Angeles, the 137 degree azimuth must be corrected by subtracting 14 degrees, so the true compass direction is 123 degrees. This corrected value is known as your declination angle.

Polarization This is the correction that compensates for curvature of the Earth relative to the satellite signal for linearly polarized satellites. This is also known as tilt or skew. Linearly polarized satellites use both vertical and horizontal polarization. To correctly receive signals on satellite transponders, your dish must be adjusted so as to receive the signals head on. Your polarization adjustment compensates for the curvature of the Earth by rotating the LNBF left or right. Note that some fixed dish configurations adjust the polarization by tilting the entire dish rather than the lnbf. A negative polarization is in a clockwise direction from vertical. A positive polarization is in a counterclockwise direction from vertical.

Step 1: Satellite Site Survey

The first step in a free to air installation is critical as it will determine your eligibility to receive satellite signals. Not all homes are capable of receiving signals as natural barriers such as trees, mountains and also man-made barriers such as buildings and other structures can block signals. Because the signal from the satellite is relatively weak, it must have an un-obstructed view of the satellite in order to receive a satisfactory signal. Also bear in mind, seasonal changes, in particular to homes with seasonal vegetation or shrubs, so you do not end up installing your satellite in a location that will be blocked when spring comes and leaves from trees obstruct your signal.
Many areas will be able to receive some satellites, but possibly not others because of these barriers. If your site survey reveals that you are not able to receive the entire satellite belt, you will need to determine the best location for your dish to be able to receive the satellites of most importance to you. Bear in mind that if a particular location in your yard is not suitable, moving the location 100 feet or more can make a tremendous difference.
Consult here pay particular attention to the satellites that you are interested in receiving. Each satellite will have an orbital slot, such as 119 degrees West. You should now choose the furthest Eastern satellite and note down the orbital location. Now choose the furthest Western satellite and note down the orbital location. The difference in the two locations is your ideal uncorrected satellite range that you will be aiming to receive. Note that your actual pointing direction will require correction due to the difference between true and magnetic North. You will now need to lookup your Eastern and Western satellite locations here in order to receive your corrected values. Select the city nearest to you and select the far eastern satellite from the list. Your "Azimuth" or compass heading will be calculated, note it down. This is the precise compass direction that you will need to point to in order to receive that satellite. Now repeat the procedure for the far western satellite.
The two locations are your corrected ideal range of view. Additionally, if there is a particular satellite of paramount importance to you, will will also want to note down the azimuth for it as well, as you will want to ensure that you can receive it, even if it means not being able to receive some others. Also make a note of the elevation of the satellite. The lower the elevation, the closer it is to the horizon. You will also need to bear in mind of your physical location. If you live near the East coast, the farthest western satellites will be much farther down on the horizon that the Eastern satellites. This will make it more likely that trees to buildings can block the signals. If you live near the West coast, the opposite is true.
You will now need a good compass. Walk outside and locate your far eastern satellite azimuth on your compass. If the elevation for the satellite is low to the ground, such as 5-10 degrees, you will want to make sure that there are no tall trees or other obstacles in your path within 200-400 feet from you. Now slowly sweep your compass west until your reach your far western satellite azimuth. As well make sure there are no tall trees in the way. Are there any tall trees in between the two points? If so, you may want to try other areas of your yard to see if a better location is available. If there are some tall trees in your way and there is a particular satellite of interest to you, you will want to compromise so as to favor reception of that particular satellite over some less important ones. Once you have located an ideal location, ensure that you will be able to install a pole in the ground at that location and also that you will be able to bury the coaxial cable from the location to your house.

Step 2: Aquire and Install Mounting Pole

You will now need to determine the diameter of your mounting pole as well as the height of the pole. Most small Ku band dishes use a 1 5/8" diameter pole. Larger dishes will require a larger diameter of pole. If you already have your dish, consult the manual or measure the mounting bracket. Your pole should be a minimum of 5' above the ground and 18-24" below the ground. If you have some obstacles to overcome, you may wish to use a taller mounting pole. Your pole will need to be secured with numerous bags of concrete to prevent movement. A general rule of thumb is one bag for every foot of pole height. Stormy locations may require more. For best results, use a steel pole which can be obtained from most steel fabricators. You will also need a 4' level and a small torpedo level.
Dig a hole 18-24" or more below the surface. Install the pole and fill the hole with concrete. You will also want to use a generous amount of concrete above the surface or you will need to bury the pole deeper. Assuming the cut on the top of the pole is a square 90 degree cut, place the torpedo level on the top of the pole and the 4' level on the sides of the pole. The pole must be both plumb (90 degrees vertically) and level (90 degrees horizontally). Check for plumb in three directions on the pole and also place some sort of brace against the pole, preventing movement while concrete is curing. You will need to check the pole for plumb several times in the first few hours to ensure no movement has occured and correct it if it has. You also need to allow 24-48 hours to the concrete to harden before attempting to mount the dish. Once cured, the dish should be solidly mounted and should not move if shook. If movement occurs, you will need to further solidify the pole with additional concrete above the surface.

Step 3: Install Dish

Installation of standard stationary free to air satellite dish
A standard installation of a stationary satellite dish or several dishes connected to a DiSc switch is fairly straight forward. Many late model digital receivers come with an on-screen dish signal meter, however you may find it far easier to purchase a low cost satellite signal finder, available from most satellite retailers for under $25. The signal finder will allow you to locate Ku band satellite signals as well as fine tune them for optimum operation.
Your first step will be to run your coaxial cable from your house and satellite receiver to your dish location, allowing for enough cable to secure it to your mounting pole and run through your dish and to your LNBF. It is always better to leave too much cable until your permanently mount your dish rather than too little. For best results, you should staple the cable to the side of your house and bury any exposed portion that runs across the ground to prevent damage. When stapling, ensure that your staple does not penetrate the cable or you will have a short which will prevent your system from operating.
Assuming that you have a pole in the ground in in some cases a mounting bracket affixed to a solid surface and assuming that you have checked the mounting pole or bracket to insure that it is both plumb and level, you should assemble the dish and LNBF mounting arm assembly. At this time, you should have all your satellite locations as well as all your elevation and azimuth settings. As your dish will be fixed in one position in the sky, you will be limited to whatever programming is on the satellite of choice. Locate your chosen satellites elevation and set the elevation angle on your satellite dish, you will find the elevation reference points on the side of your dish. Bear in mind that you may still need to fine tune it after you have located your signal. Mount the dish to your mounting pole, run your coaxial cable to your LNBF, set your satellite dish polarization by adjusting or rotating the LNBF to the required setting and secure your LNBF to your dish. Most dish manufacturers include a polarization scale that you can use as a reference. You will still need to adjust this setting later, so tighten the LNBF just enough to prevent movement. If you are using an external signal finder, connect the LNBF end to the LNBF and the coaxial from your house to the receiver side of the finder.

Step 4: Free to Air Receiver Setup

You should now have your dish mounted temporarily outside and your coaxial cable connected to it. The dish should be set to the elevation and polarization that you calculated earlier. Connect the coaxial from your satellite dish to the receiver and connect the receiver to your television. Consult your receivers operating manual for the setup setting. Initial satellite setup varies from receiver to receiver, some are easier than others. Follow the setup procedure and setup the satellite from which you will be receiving programming from. Once you have this complete, you will want to return outside to your satellite dish in order to locate your desired satellite.

Step 5: Satellite Dish Alignment

Assuming that you have your elevation and polarization setting correct, and assuming that you have a signal finder connected to your dish, set your signal meters sensitivity to the half way point. Move the dish to the far left and slowly rotate it right until your signal meter picks up an active signal. One you have locked onto an active signal, you will need to adjust the signal finders sensitivity so that you can find the optimum signal strength. Once you have peaked the signal by adjusting the dishes azimuth, you should return inside to insure that you have locked onto the correct satellite. Peruse the available satellite channels and compare them to your satellite channel reference. If you are locked onto the wrong satellite, you need to return outside and continue searching for the correct satellite. Once you have the correct satellite, you now should return to the on screen dish tuning meter and return outside. Once again, ensure you have optimum signal by minutely adjusting the sign from left to right until you have peaked the signal. Once you have achieved the optimum signal, you should lock the dish into position by securing the azimuth adjustment bolts which secure it to your mounting pole.
You now need to loosen the elevation bolts so that you can slowly adjust the dishes elevation for optimum signal strength. Once again, you may need to adjust your signal finders sensitivity to achieve this. Slowly move the dish up and down again until you have peaked the signal strength and lock the dish into position.
The final setting is to fine tune the polarization setting. Some receivers have a seperate meter for this, consult your manual for details on accessing this feature. You may find it easier to have a person on the inside watching the meter while you are adjusting the dish on the outside. Loosen the LNBF and slowly rotate it clockwise and counterclockwise until you have achieved the optimum signal. Once complete, disconnect the signal finder from the LNBF, measure the final coaxial cable length, allowing a short drip loop to hang from the bottom of the LNBF mounting arm and permanently secure the LNBF and all other mounting bolts.
Your final signal strength should be in excess of 60% or more. If it is below that level, you will need to check for obstacles in the satellites path, such as trees. A low signal will cause outages in heavy rain or other weather. This is known as rain fade. If you have a tree in your way, you my find upgrading to a larger dish is necessary. This is also true of satellites that do not specifically target your area in their footprint.
Once you have achieved a good signal, congratulations and enjoy your free to air system.
__________________