So awhile back I purchased one of these:
Mikrotik OmniTIK UPA-5HnD Weatherproof Outdoor AP with Dual-Polarized Omni Antennas
Went to install it and before I did I tested it. Connected the dongle to Ethernet 1, and powered via AC, nothing came on,
no LED, no apparent response when I connected my laptop to another ethernet port (or the same one).
Checked AC adapter, it's putting out ~24v.
So figuring maybe I bought a lemon, and its way too long ago to return -- I bought a second.
Same behavior, swapped AC adapters, dongles, tried resetting...
Odds of two bad hardware units is pretty low --
So.... I'm either doing something completely stupid or there is some other indication of powering on -- or I'm missing some hidden power switch somewhere.