How I set the Declination on my antenna

Vallenato said:

Hello Everybody
How I set & adjust the "Declination" of my antenna..I am using sadoun 1.8 mts. Static no Motor or actuator. This parameter "declination" is "movable" (like Azimuth & elevation depending the satellite) or Just one Time and never Touched.. I am trying to aim my south at galaxy 19, 97.0W.. after testing 97.0 W and find my true south I wish to aim to 58.0W..
Declination parameter is the same on C band and Ku band?..For example If I got 58.0W on C band and if I want signal on Ku band on 58.0 W (switching my LNB) the declination parameter should be the same??
thanks in advance

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Once Declination is set properly for your location on Earth for your true south, you never should have to change it again. Even for a non-polar mount dish. That's the one adjustment that is true for.

Yes, you have it correct. If your elevation is 57, you subtract the declination for that, and you'd get 51.6

Think of it as your dish has to point DOWN a little, to get into the Sat arc which is at a certain height above the equator. Otherwise it's more or less pointing off into space.

http://www.geo-orbit.org/sizepgs/tuningp2.html#anchor469886

That's a good website for you to study. It'll teach you a LOT.

You wrote "No motor or actuator" ?

Declination is only useful for scanning the arc, otherwise known as the Clarke Belt. If yours is a static mount, meaning it will point at only one satellite and be fixed on it, then you only need to be able to hold your dish on your pole and have an elevation adjustment. It doesn't matter what your declination is now set at, or even if you don't have a declination adjustment.

If you are not using a motor, declination adjustment is no moire than a curiosity.

Lone Cloud said:

You wrote "No motor or actuator" ?

Declination is only useful for scanning the arc, otherwise known as the Clarke Belt. If yours is a static mount, meaning it will point at only one satellite and be fixed on it, then you only need to be able to hold your dish on your pole and have an elevation adjustment. It doesn't matter what your declination is now set at, or even if you don't have a declination adjustment.
If you are not using a motor, declination adjustment is no moire than a curiosity.

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I think the Sadoun dish is a polar mount. He might be using it fixed with a bar, but the polar mount settings still apply just to keep things less confusing. Even if it is a fixed dish, it doesn't hurt for him to learn about Declination, and why it exists. He might just want to upgrade to a polar mount real soon!

primestar31 said:

I think the Sadoun dish is a polar mount. He might be using it fixed with a bar, but the polar mount settings still apply just to keep things less confusing. Even if it is a fixed dish, it doesn't hurt for him to learn about Declination, and why it exists. He might just want to upgrade to a polar mount real soon!

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Sure, knowledge is good, but he appears to think that declination is necessary for a one satellite, non moving dish. He is deep in calculation, angles and adjustments. Rather than making things less confusing, they are more confusing.

He needs to understand that the satellite he wants is fixed in a certain location in the sky relative to his location, and that if he aims his parabolic dish at it accurately, he will get the signal. The declination adjustment could be set for the value at the north pole or the equator for that matter, but as long as the face of the dish is aimed at the right point in the sky and held there, he will get his signal.

I disagree that doing the declination on a fixed mount is simplifying things.

click above attached photo to see how to adjust 1) Declination 2) Latitude/Elevation on that Sadoun Polar Mount 1.8 dish

In case you decide to add an Actuator/motor for more satellites

If it's on a polar mount, set the angles as shown on the picture above. (angles are set with the dish set to the highest point in its travel on the polar axis)
Use the modified latitude angle.

Adjust/set the declination corresponding to your latitude, and don't touch it again.
Use the actuator to set the dishes elevation for a satellite near the horizon*. Then adjust the Azimuth (Twist mount on pole ) to acquire the satellite. Then use the actuator to move towards the center, Look for the satellite nearest the center of the arc that you can. Adjust the elevation there. Recheck the satellite near the horizon and re tweak the azimuth.
Zenith= adjust elevation. At the Horizon(or as close to as possible)= adjust azimuth. Don't mix the 2, and don't mess with the declination after it's set.
May have to repeat a couple of times, but I think this will get it on the arc.
*Use a straight edge vertical across the face of the dish. Elevation is the perpendicular.

Vallenato said:

Thanks for your support Primestar31 & Lone Cloud

Mi question is because long time ago, I did aim to pass 9 58.0 w and good results, and next I have switched to Nss 806 40.5 W and excellent results (I never touch the declination settings) and right now I am trying to move again at the new satellite intesat 21 at 58.0 w and nothing. I am missed..lol.. I have moved all settings and nothing (include declination).. I come back to the "Bud- School" to read and understand the meanings of the parametres to find What i have wrong.. I have read that is more easy to aim the satellites when you find your true south (to move and come back) but my problem is that my direction to the true south is totally blocked with a tree.
Maybe I will get an actuator in the future but no now
thanks

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It really doesn't make sense for you to worry about what you might do in the future. I can assure you that you would be incredibly lucky to be able to just strap on an actuator motor and get the entire arc.

If you must know, declination is a function of your latitude. It is an adjustment that, once set, never changes, because your latitude doesn't change. If you are somewhere in the 48 states of the US, your declination will approximate five degrees.

As far as your southernmost satellite is concerned, you might be able to attach a protractor to your dish somewhere, so that ninety degrees will be your zenith. Then get the satellite you are going for and see how many degrees east or west it is of your location,
then move your dish that many degrees using the protractor in that direction and tighten it there.

Then try spinning it on the pole until you get the satellite you want.

The problem with all that is, a fixed mount doesn't even need a plumb pole. It can be crooked, but as long as it's firm, it will work. If you are looking to go for the arc though, even manually, you need a pole that is straight up and down and solid.

Still, in my view, it isn't worth worrying about any of that until you are ready to go with a motor.