Hi,
I have the same problem, radio power of mANTBox ax 15s est very poor, in comparison to what Mikrotik claims.
My old year 2016 indoor WiFi router Asus RT AC66U with 3 small antennas, from inside, transmits outdoor almost as far as the mANTBox ax 15s. See the tree http://forum.mikrotik.com/t/new-in-routeros-v7-15-3-especially-on-mantbox-ax-15s-i-have-troubles/177708/1
I wonder, if there are users who have purchased this product and can use it at distances of 100, 200,… 500m?