From my FAQ:
Satellite positions are described as the longitude of the place on the equator that the satellite hovers above. 19e means 19.2 degrees east, which finds some Astra satellites about 35000km above the Congo basin, with many FTA German broadcasts. If your dish isn’t aimed at it and you want to watch a channel on 19e, you need to move the dish, either manually or maybe with a motor or jack. A good signal meter (either on-screen or connected near the dish) and a compass is usually enough to aim a dish.
Satellite signals can only be picked up within their transmission “footprint” so check coverage first. For channel frequencies and reception reports, see “What other resources are recommended?”