Antenna requirements for the Skytrax200 (ST200), as of 2021:
Pilots adding the ST200 must ensure they are working with an Avidyne dealer to ensure they have the correct antenna.
When adding the AXP340 and the Skytrax200:
You must install a sperate antenna for the ST-200.
Avidyne does not recommend a Duplexer, as this would not block the output power from damaging the receiver input of the ST-200.