Just to make it clear: PowerFLARM will not only show Flarm and 1090ES ADS-B traffic, but also all transponder- equipped aircraft (move C and S) as non-directional "threats" with altitude and approximate range (if being interrogated by SSR/ATC. So the short answer is: get a PowerFLARM, and back it up with a mode S transponder is you can.

Kirk
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