Originally Posted by TJExcalibur   OK its like this then. If the motor is parallel to the dish it would not be possible to track the arc. So the brackets allow the motor to be set at the correct angle and the brackets are the adjustment for the offset dish. Must admit I am unable to see the difference but the proof of the pudding etc......
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If your motor is horizontal, it will track a straight line in the sky, which if you were lucky may possibly pass through two sat. positions.
If you were on the equator, you would need to set your motor to vertical, pointing due south or north since you are in nomans land, and set your offset dish leaning backwards about 25deg (average sort off ofset for dishes) and you would then be able to track the sats.
As you are not at the equator, you need to set your motor to suit the lat. you are at, pointing due south when at the zero position.
You need to apply a correction for the curvature of the earth, (about 7deg for these latitudes) added to the offset angle of the dish. This gives typically 7deg + 25deg = 32deg. You then need to tilt the dish forward 32deg. This is approx the same as the inclination of the motor, and is why the dishes are close to vertical when at the top of the arc.
The dish will then track the arc, and will automatically apply the right amount of skew to the LNB and dish
The two things which can be measured and must be set accurately are the inclination and due south. Because of manufacturing tolerances, difficulty in measuring/knowing the offset of the dish, mounting position of LNB etc. some degree of fine tuning is usually required when finally setting up, but if you have set the motor accurately, all adjustments should be on the dish mounting.