Herelink & Holybro PX4


I’m using a Holybro PX4 and Herelink HD Transmission system.
On the PX4 is running ardupilot but the herelink ari unit doesn’t seems to be booting. I’ve connected the Air unit to the SBUS RC and Telem1. In Missionplanner I’ve configured Serial1 as Mavlink (1) with a Baudrate of 57 000 but the LED’s of the Air unit are still off.

Does anyone else had the same issue and knows how to slove it?

Thanks in advance