Solar outage time is here again-great time to reposition dishes!

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anik

SatelliteGuys Pro
Original poster
Aug 28, 2004
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Solar outage time is here again - this is the time of year when the sun moves into a position directly behind the satellite arc. It will happen on various days depending on your latitude but on one day in particular, and a few days on either side of that date, the sun will be directly behind (or nearly so) each satellite in the sky at some point during the day. At that time your reception will blank out (or, on an analog signal, turn to pure noise) as the sun overpowers the satellite by several orders of magnitude.

The thing is, if you know what day that happens, that's a great time to figure out where your dish SHOULD be located in your yard (hopefully you're not one of those people who drills holes in your roof!). If you have (or plan to have) a motorized dish, then what you want to find is a place that is in the sun all day (or at least for the part of the day that the sun is behind the satellites you most want to receive), at the height as which your dish will be located. In other words, lets say you plan to put your dish on a metal pole and the center of the dish will be 6' above ground level. Get a stick or pole that is 6' tall, optionally tape a paper plate or similar object to the top, and go find a place that you think is in the sun all day. Prop up the pole so it stands straight up and watch the SHADOW of the top - if it's clearly in the sunshine all day (with no shadows from trees, buildings, other objects, etc. coming within a few feet) then that is a good spot.

If you just want to receive a single satellite, then you do the same but now you are only concerned with shadows at a particular, exact time of the day. More on that in a second.

If you have an EXISTING dish already set up, just look for shadows falling on the dish. Shadows are very bad, even the shadow from a few leaves will drop your signal strength tree-mendously (sorry about that). :D

Now the secret is in knowing what date and time to look. First you have to know your exact latitude and longitude, and then if you are only interested in a single satellite, the location (in degrees) of the satellite in the sky (otherwise you'll probably want to calculate for at least the easternmost and westernmost birds you plan to receive, so you'll need their locations). You can get those from Lyngsat, or any reference showing satellite positions. Once you have those, there is a very nice calculator that uses Java and Javascript at http://perso.numericable.fr/~gjullien/satellite.htm

The other way is to use a very old program called SUNOUT which was written in 1988(!) by Warren Small - you will need to run this in a DOS box on your system (and I'm honestly not sure if it will run at all under Windows XP unless you can grab an MSDOS emulator somewhere, but it WILL run under Windows 2000 and earlier. Maybe someone could let me know about that). One drawback of this program is that it expects all satellites to be on an exact whole degree position, so if for example you are trying to calculate for a bird at a half-degree position you'll have to run it for the two closest integer positions and extrapolate the results.

Remember that you can copy and paste from a DOS box by highlighting the text you want to copy using the mouse, then hitting ENTER.

Once you have the date and time to look for a shadow, try to be precise - use a precise time standard (hopefully your computer's clock is set to one???) or if you have a shortwave radio, use WWV or WWVH to get the time. In a pinch you can call 1-800-555-TELL and say "TIME" and that will be fairly precise. Being off by even a minute or two can cause the sun to move quite a bit in relation to relatively close objects, so if you look for shadows a minute or two early or late and there is a very close shadow it could make a difference (of course, if there's nothing but bright sunshine for ten feet in any direction from your dish then it won't matter if you were a minute or two late)!

For more information and advice, try using Google:
http://groups.google.com/groups?q=%22Solar+outage%22

Hope this helps someone.
 

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