Maybe Rally. Not sure I follow...
But anyway, just by way of being a f'rinstance. Here is a potted history of one very successful amateur from years ago:-
Grote Reber was the father of radio astronomy, being the first person to build a "big dish" antenna for the purpose of mapping the sky at radio frequencies. He discovered many discrete radio sources, and he mapped the band of bright radio emission from our Galaxy, the Milky Way.
Reber came to Tasmania in the late 1950s because of its unique location at high magnetic latitude in the southern hemisphere. He spent 40 years studying low frequency emissions with telescopes he built himself, first in partnership with the University of Tasmania School of Physics,
and later on his own at Bothwell. His accomplishments are remarkable, not only in radio astronomy but also in electrical powered transport, in carbon dating of aboriginal settlements, and in the patterns made by growing bean plants. His creative vision had no limits...
I've seen photos of his array. Easily measured in acres.
http://www.groterebermuseum.org.au/index.html