For an Airmate connect the Cleanfeed output of the Airmate to the to Cleanfeed output of the Hybrid-1.
Connect the to Mic input of the Hybrid to a Mic input at a desired Channel.
Set the jumpers (Cleanfeed on/off) J7 triple channel and Telco) of all the other channels to “On” and the channel where the Hybrid-1 is
connect to to “Off”.
https://www.d-r.nl/assets/airmate-usb-manual-2.13-mail-smd.pdf