Recently started to test run a new preamplifier with ceramic filters and have seen a dramatic increase in the counts recorded on my FlightAware coverage map.
AirSpy is the US seller of the filter/preamp. A less expensive preamplifier only version is available. I would guess that the FlightAware 1090 MHz filter could be inserted in line with the preamp non filter model.https://store.uputronics.com/index.php? ... duct_id=50