900 connection randomly drops

So I have a 900 connection. It works great when it works. Usually runs -72ish at the SM reading -70 at the AP. RSSI in the 1500’s.

I originally had the SM side connected to a 18dBi Yagi. I thought maybe the beamwidth was too narrow so I switched down to a 9dBi Yagi.

Radio is located about 8 miles out.

Several times a day it completely drops. The SM goes to scanning and can’t pick anything up. Noise floor shows in the -90’s

I’ve tried switching all different channels on the AP also. I have about 6 clients on this AP - none have the issue.

I just turned off color codes tonight.

Any other ideas?

I also just set the SM to come up in operation mode instead of align mode when no link.

The outages usually last anywhere from 30 minute to 2 hours.

I had this problem with an SM recently. I just replaced the SM, problem seems to have disappeared.

No such luck. Replaced the SM today and still have identical problems.