The dish is across at its opening and deep.

Set up the problem so that the vertex of the parabola is at and it opens up.

Then the equation of the parabola has the form :

Since the parabola is across and deep the points on the parabola is  and .

Substiute and solve for :

Where is the distance from the distance from the vertex to the focus.

Therefore the receiver which is located at the focus is  or .

from the base of the dish along the axis of the parabola.

The receiver should be placed or from the base of the dish.