Now I had already tried the following before the temperature dop:
Downgrading the switch to v1.1.8 no effect so I upgraded it back to v1.2.2 again
Changed the POE from 48VH to 48V which rebooted the radio as I have to turn the POE OFF to change it from 48VH to 48V and no effect, still 100M
Changed POE back to 48VH which of course rebooted the radio again and the link remained at 100M
Now after the storm reduced the air temperature by almost 20F the radio's Ethernet connection now links up fine at 1G after a radio reboot. I am also sure that the grey conduit the wire runs in was much warmer than 88F as it was in direct sunlight. People do not think it but temperature effects wired communications as well, and even fiber optic to a very very very much less degree.
So what does this tell us, I am going to say that the added temperature reduced the characteristics of the copper Ethernet cable (dB loss or cross talk between pairs) which prevented the link from obtaining a 1G modulation.
Now the cabling in question is 100' of cheap indoor Cat5e inside a grey conduit up to a junction box and then 10' of Toughcable out to the radio.
However this particular cable run in question is the same cabling I use the whole way up the tower to 200' into a junction box and then 20' out to an AF24 and it maintained a 1G connection.
Now granted this particular cable run that the MIMOSA is using may have been damaged during install and the wire to the AF24 was not, so many variables at this point.
But my original "guess" that temperature was a factor "appears" to be correct.
I would be interested to know the Ethernet transformer characteristics of the MIMOSA and the AF24 to compare as there are different levels. But this could be just the cabling and that is the most obvious reason. There is also other factors such as the PHY that was used and the PCB traces on the PCB for that matter, do they maintain the proper 100 ohms of impedance throughout the entire operating temperature range which is important! Many manufacturers do not do this correctly and for 10/100 who cares but it becomes crucial for 1G at higher temperatures. PCB's just like anything else expand and contract so if your on the edge at room temperature you suddenly find yourself in trouble at 55C. But we are getting ahead of ourselves, yes these are factors that reduce a devices ability to link up with poor cabling under poor conditions but it is probably just poor cabling.
The temperature variation can also cause the RJ45 jack to fit differently changing the tolerance or contacts.
The good news is there appears to be NO hardware damage as was one possibility and there is no incompatibility between MIMOSA and Netonix.
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