Just got a Pi setup running again after a year or so offline. Using new Pi 3B+, Raspbian and the Piaware 3.6.3 add on.
Was working fine, it’s still reporting it’s hearing AC but, all of a sudden, no ADS-B data being received. It’s as if nobody’s reporting their position. Get speed, alt, all that good stuff but no positions in the last 36 hours at all.
I’ll be taking a look at that as well. Using a decent antenna and the Pro dongle but positioning ain’t the greatest. (Even so, though, it was getting positions just like that before… go figure.)
You can also try another power supply.
Insufficient voltage can also cause the receiver to not work as well.
RPi 3 Official Power supply is recommended because it provides 5.2 V.
You can also hook up the dongle via a powered USB hub to ensure good voltage for the dongle.
The receiver itself generates interference and shouldn’t be in proximity of the antenna.
Also it’s good as you found out that the receiver is not in the horizontal plane of the antenna where it has the strongest reception.