STX 165 :: Is this unit ADS-B compatible? Nov 28, 2014 | Is this unit ADS-B compatible? 1 Comment admin on November 28, 2014 at 6:28 pm Sandia STX165 Mode C TRANSPONDER with a UAT / WAAS GPS will meet the 2020 ADS-B mandate when interface with a compatible UAT transceiver. The STX currently interfaces with MGL, uAvionix and the Garmin GDL 82 to provide a compliant solution. When installing ADS-B the FAA recommends against installing both 1090 ES (Mode S) and UAT as they can conflict with each other and transmit your aircraft position twice.