We have been working to understand and mitigate problems concerning SensorStation (mainly V3) FUNCube malfunctions. SensorStation USB hubs are prone to overheating, especially in hot conditions or when running 3 or more FUNCubes. This leads to FUNCubes being “kicked-off” periodically, effectively cutting off 166 radio data until the station reboots. This can be seen in the receiver timeline when evaluating antenna activity. Regardless of whether your SensorStation has undergone these FUNCube drop-outs, we have the following recommendations to ensure your station/s run as smoothly as possible:
Make sure you are running the most current Disk Image (new V3 stations should already have this installed)
Set your reboot schedule to weekly
Keep your SensorStation shaded / cooled, and housing them in air-conditioned rooms is the most effective!
I’m curious to hear if you’ve found a sort of “cut-off” temperature after which these problems start occurring, and whether you know if this is an issue that’s related specifically to USB hubs, or if it can also occur to FunCubes plugged directly into SensorStations. Overheating issues are something I’ve worried about for our setups, which are in relatively small boxes exposed to directly sunlight, but I haven’t seen (and therefore haven’t been able to test) overheating issues in our setups.
Lynn, I can’t say what the cutoff temperature is, because that will also depend on how many FUNCubes / USB ports are plugged in, which is also tied to the cell/wifi modems. And yes, when they are confined in a small box with no air circulation outside in direct sunlight, they can easily overheat. Though, we observe this more often in the southeastern US (where I am based) far more often than in the northeastern US / Canada. You can follow the instructions in the document to look at past data to determine if your stations have dropouts or not. And I’m not sure what you’re asking of USB problems or FUNCubes directly plugged into the SensorStations, because they have to use the USB ports. FUNCubes are quite power-hungry radio dongles, and thus they can easily overload the USB hub. Other radio dongles (RTL-SDRs) don’t appear to overwork the USB hubs nearly as much, but they are also far less effective for detecting tags, and thus we don’t recommend using them.
Patrick, there is a photo and more instructions / details in the document I attached. But here is another example of what heat sink application looks like, circled in red
