Hello, trying to get my head round this one. My 2860ac has 3 antennas, in the settings I have 1T1R or 2T2R (same as my ap902) but no 3T3R. So what is the 3rd antenna used for? Alan

Maybe that setting is only for 2.4Ghz ?

http://www.draytek.co.uk/support/guides/kb-wlan-replacing-antennas

Thanks. So going by the link you sent my 2860ac uses the 3 antennas for transmit and receive. But by the specs it only uses 2 antennas for mino, which made me wonder what the third was for. Also the 2860ac only runs at the same speeds as my ap902 with the same settings which also makes me think it only uses 2 antennas. Alan