Thank Eric. This is cool info and gives me a strategy to look into these devices. This is my ISP's setup for wireless and there are a lot of trees here where the antenna is pointing through.
I just figured if I could just point out some problems that I can get my isp to resolve after I read more about your "few things".
You may want to tread lightly when giving advice to your ISP on what to troubleshoot. Some ISP's and people do not take kindly to being told how to troubleshoot, run or make changes to their networks.
I use to complain that I don't think it is helping with Yagi Antenna shooting accross the roof, so had him move it, they did but then wife told him it wasn't helping and now its pointing thru some trees. I mentioned to ISP that you have to be missing something but he got to the point of well I think we just can't service you and wanted to just remove me as a customer. I gave up trying to get them to get the setup more stable. Satellite is my only other choice.
I'd approach your ISP and explain the issues you're having and explain that you're willing to throw down some money, beers, whatever it would take to schedule some time for a seasoned tech to come out and look at your system. You can usually get a reasonable WISP to help you out if your patient, understanding and generous. If satellite is your only other option, you will need to be extremely diplomatic if you don't want to be disconnected from their system as there's no competition.
BTW would the ethernet cable being 30 or more feet away from POE give attenuation? I read a little on that and it said I should have as short as possible a cable from antenna.
No, a distance of 30 feet is just fine for an ethernet cable (PoE to the radio). Check to make sure the PoE data port is connected to your router or computer at 100mbps FDX thought.
What you want to avoid is attenuation at the antenna or between the antenna and the radio. In basic terms, attenuation is something that reduces or blocks a signal. In regards to digital radio equipment, you typically want as small a jumper as possible between the radio and the antenna. As to your attentuation and what I was talking about, this would be probably caused by large number of trees in between the ISP's transmitter and your client radio. While I don't have enough information and it would be really handy to see your re-reg numbers at the AP, the SnR you have is good, and doesn't indicate that you're having a noise problem (at least not in the moment you took that screen shot). It would be interesting to see if your modulation drops and your SnR gets worse at certain times of the day.. which could explain your drops.
900Mhz can be very tricky but there are things that YOU can do without having your ISP come visit you. Simply spending a day temporarily moving the antenna/radio to different spots on your roof or property to try to find a better signal. It will probably be easiest to have someone help you with this, like your wife, that reads off the signal to you as you try different locations. In regards to the signal, lower numbers are better (e.g a -65dBm signal is BETTER then a -75dBm signal). Sometimes with 900mhz, higher isn't better, sometimes shooting through the tree trunks at the bottom of the trees is better then shooting through the leafy canopy. Lastly, you could buy yourself a larger yagi antenna and attach it to the client radio yourself, it's very easy to install. You should let your ISP know you're doing that however as they might get mad if you change antennas on their equipment... they really shouldn't care as it's saving them a trip and the cost of antenna, but yeah, let them know anyway.