Hi there, i am currently investigating a strange Problem and need someone who has similar setup to verify.

Scenario:
2x SXT, ROS 5.18, 400m Range, LOS, both sides set to 20dB tx-power, both chains, datarates manual up to MCS 12 (13-15 are NOT used), conntrack disabled

Doing a bw-test (only one direction) over them (not from them) with a packetsize of 500 bytes is working well. Getting 97,5 Mbps.

Now just use MCS13 and do the same test (with 500 byte packets). CCQ is going from 10% to 95% all the time, sometimes the link is disconnecting (control-frame-timeout)

it will go up to full speed, then fall down to < 10 Mbps and will to very strange things. Disabling MCS13 again and everything is working well again.

I disabled MCS13 and above when i notice that i have a lot of disconnectes when using them, ccq is never at 100% but with disabled MCS13 i get 100% all the time.

can someone do similar tests and let me know the results?

regards, Joerg

i have a similar issue with a pair, to me it feels like the one polarity is giving me issues, if you look under registration from both sides and you have that listed side by side does both show all the rates unlocked when u have it set to rate selection=advanced and all of them on auto?

if the wireless link isn't working stabel at mcs13-15 it will not go to 100%, bt if you disable MCS13-15 and the link reaches MCS12 and works good then it could be 100%. As ccq depends on what max data-rate is enabled on the link.
In you case maybe there are some interference that effects MCS13-MCS15 data-rates - those data rates use 64-QAM modulation and maybe it isn't so stable in your area.