The transmission tower was built on the Donnerskopf around 1960. Since 1997 the facility has belonged to the Association of Christian Scouts and Scouts Hessen, which uses and rents the area as a scout center and youth education center.
The Donnerskopf lies on the watershed between the Lahn and Main, two tributaries of the Rhine. Donnerskopf is a mountain in the Rhenish Slate Mountains.
That's what "WikipediA" says. Honestly, otherwise I wouldn't know.