Intresting information and pictures showing ADS-B reception from a customer:
Concerning the antenna discussion I have a few screenshots from Denmark and Germany:
and my problem with the Berlin TV Tower.
With the included Radarbox antenna in a height of 3m a.s.l. on the roof of a sailing yacht cabin I have had coverages of up to 180 nm.
Pic 1: Four hours reception in the port of Gudhjem on Bornholm Island with a 70m hill in southwest direction
Pic 2: 30 minutes monitoring during the departure from the port of Gudhjem on Bornholm Island
Pic 3: Position about four hours off Christiansoe in the northeast of Bornholm Island
My home location is only a few kilometres from the TV tower in the centre of Berlin. The antenna I use is a GP1090 by WIMO mounted at the side of an antenna mast and there are 35 metres of Ecoflex10 cable between antenna and receiver. The following pictures show the HF spectrum and signal strengths on the roof of my apartment house:
Pic 4 shows the spectrum of several VHF radio stations, TV stations and other signals emitting high power and jamming my preamplifier
Pic 5: The selectivity of the GP1090 antenna suppresses signals outside of the 1090 MHz band
Pic 6: The AS 1090 preamplifier eliminates even more signals and raises the signal levels in the 1090 MHz band.
Pic 7: GP1090 - coverage without preamplifier
Pic 8: GP1090 - coverage with preamplifier and a little shading by the antenna mast in NE
Pic 9: GP1090 - coverage with preamplifier and shading by the antenna mast in WNW
Pic 10: This picture shows the shadows of the next mountain ranges: Harz in the southwest, Fichtelberg and Keilberg in the south, the Giant Mountains in the southeast and the antenna mast in WNW