Hey gang, FTA newbie here. Bought a camp in the mountains of Pennsylvania with a DN500 hanging outside (think it's 18"). Bought a $40 eBay Pansat 2700(not a clone) and was perfectly happy with having only ION TV & NASA TV. Since they have been removed, I've toyed with pointing to some different birds with all the info I've gathered from these threads, and the sites they have led me to, but have not been successful with any channels. I'd be really satisfied if I could just pick up an ABC News One or Ohio News Network (actually ANY english speaking channel) or even some wild feeds. Any chance of that happening with an 18" dish, or is (min)90cm a must? Also, there's no Diseqc switch on the DN500, coax strait from the 119w side of the dual LNB. Any point in trying to get input from both? Any help is GREATLY appreciated. Thanks!
Duke,
Welcome to SatelliteGuys!
The previous responses to your questions are on target. The DN equipment won't be usable for FTA - at least not reliably. A larger dish reflector is required and the LNBF needs to be of the LINEAR polarity type.
DN uses circular polarization and a stronger power level and the satellites are separated in the sky by 9°, so you can get by with using the smaller 18" dishes.
FTA sats use linear polarization, transmit with lower power (and thus can be located closer together than 9° - they can be 2° apart) so you need a larger dish to capture their signal.
In reality, there can be several linear FTA satellites at near the same orbital location in the sky. For instance, Hispasat at 30.0°W. There are actually three satellites there now, Hispasat 1C, 1D and 1E (soon to be on line). These satellites are truly three unique physical masses of metal and electronics, so they obviously cannot occupy the very same space. They are actually separated slightly. One might be 29.96° and another 30.03° or something like that. But, for all intents and purposes to us from our viewpoint on earth, the receiving station, they are all at 30.0°W. So, they all appear to be the same satellite, even though they are three unique satellites positioned there.
Now, if it is the intent to keep two satellites separated (so that when you scan one, you don't scan the other as well) then they have to position them further apart. For linear sats this spacing is 2° and for the circular satellites, it is 9°.
This information is all for your benefit to understanding the differences between specific sat transmissions. It is only one little piece of the basic foundation that you will need to know in order to understand everything.
So, what is the difference between linear and circular transmission? Well, a simple analogy will get your mind to visualize it. In linear polarity, think of looking through a gun scope where you see the vertical and the horizontal crosshairs. The antenna on the satellite in space is orientated the same way, like a big "+" sign. So, the vertical polarity signals are resonating in a vertical line - up and down and the horizontal polarity signals are resonating in a left to right fashion.
In order for your LNBF to capture those signals properly, the vertical crosshair in the LNBF on your earth based antenna must line up with the same vertical axis as the antenna on the satellite in space. And the same for the horizontal crosshair or axis. So, envision the linear satellite in space to be a large "+" target and you must dial your LNBF in on it to align the V and the H crosshairs with the "+" on the satellite. If the satellite is directly south of you, the "+" sign stands straight up. In the northern hemisphere, if the satellite is more to the east of you, the "+" appears to lean over to the left or to the east. So, to track that change properly, you have to tilt (or roll) your gun scope in the same direction to maintain the alignment. This is what is called "polarization" of the LNBF.
Actually, the components of the "+" remain perpendicular (|) and parallel (-) to the circumference of the earth, but when the satellite is viewed from different locations on the earth's surface, it appears to be leaning or tilting unless it is due south of you. To compensate for this angle appearance, you (or your LNBF) must lean over in the same direction to view it as if it is still upright.
Circular polarization is much different. The signal appears like a corkscrew, twisting CW or CCW as it eminates from the satellite in space and down to earth. Like putting English on a pitched baseball or a rifle bullet that spins as it is exiting the muzzle of the rifle. Now, the polarization of the LNBF no longer matters. The LNBF can be twisted in a circle to any position and still receive the signal. So, here you can think of your LNBF like a "funnel" for the signal. It doesn't matter how you rotate the funnel, it captures the transmitted signal the same in any position.
These same polarization rules apply to C-Band as well as Ku-Band signals.
Now, with your new cabin, your main trouble is going to be with having a good LOS (Line Of Sight). If there are trees or hills and mountains in your way, you won't get one specific satellite. If you are atop the peak of a mountain, you have no worries except the trees. If you are down in a low valley, you may find your LOS limited by the mountain ridges. Depends on the terrain of course.
For Ku-Band, a 75 cm dish might get you by acceptably. You can go up from here to a 1.2 M dish to amplify low signals better and to reduce rain fade and provide for better separation (less interference) from adjacent satellites.
A 76 cm Winegard DS-2076 dish is really quite acceptable for the mid-section and more southern United Sates. It is inexpensive, it is lightweight, it is built tough, it is easy to handle and it is designed well. Everyone states that bigger is better, but that all depends upon the specific application. I have several of these specific dish models (DS-2076) and they are absolutely fine for my purposes here in Nebraska. Now, I have also installed a 1.2M GeoSatPro dish which gains me a few more lower power channels and improves my reception on the ones that I was getting with the 76cm Winegard.
I would not go less than 76cm nor do I think that it is beneficial to go larger than 1.2 M for Ku band in the mid section of the country. Somewhere in this range you should find a dish size that fits your niche.
I hope that my information will be helpful to you. If nothing else, you will store some of this information in your head for just reference purposes.
RADAR
