Hi Tamas , i dont know the technical specs of the antenna i attached . It was from a old fritzbox router. The connectors on pcb are female . Mini U.FL should fit well .

I faced same issue , installed Mikrotik HAP AC2 in room 1 , room 2 , with one wall in between and 8 m away, no signal. Opened the box , relatively easy to open, found the two antenna connections , fitted external antenna from an older router and yes ! 100 mbps at the router , thats the provider spee...