So here’s the scoop. Location one is heavily treed, perhaps 6 or 7 nm from KRDU airport. Land is at 350-400 ft above sea level , sloped upwards toward the West, and there are numerous nearby residences and associated competing wifi, cell and other RF clutter. Suburbs. Best sky view is towards the NNE in terms of obstacles. I’m not done with my setup there but it is not at all ideal.
Location two is near Beaufort NC, wide open at nearly sea level, with only a couple of tall condo complexes to the SSE and SSW to block line of sight, Great open sky but compromised some by low elevation- I cannot get an antenna above 12 feet or so above ground level, and that’s only about 7-9 ft above mean sea level. I’d probably have to elevate the antenna 150 ft to overcome the condo blocking, so its a moot point.
As good as location two is in terms of reception, part of that great reception/ range is maybe hindered by the fact that a great percentage of the surrounding air traffic goes on over land on a NE/SW track, leaving the East quadrant with relatively sparse traffic that flies over water ( transatlantics, Caribbean, etc.)
Inland, a similar situation might capture heavier traffic on all points of the compass - so that’s learning point number Two for me: you can have great ADS-B reception and not have planes that fly where you are able to see them. 80+ percent of the traffic at that location is in the Western half of the map. ( from about 200 degrees clockwise towards 20 degrees) As I type this, the Eastern half of the map is nearly empty of planes.
Its all a work in progress.