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Over Apr 10,11 and 12 it seems to come alive in the warmest part of the day,
(at temps over 10C) and then fails as the temp falls in the evening. See plot below.
Here is a dump of some recent data (times in GMT).
Looks like the processor is getting reset, printing out its calibration
information when it boots. Perhaps the power is dropping out?
Corroded connection?
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