I have read some of your threads, and know you really want to have a successful hatch. 

Just wanted to suggest  as I have suggested to others.  Checking accuracy of an electronic thermometer is easily done with a   Drug Store people thermometer.  The range is at the correct level.  People fever thermometers are quite accurate.
I know that the Old skool thermometers  are much replaced with the New skool electronic ones.
The older type can be place whole inside incubator, and can be viewed without pushing a button to light up.
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BTW,  I purposely spell  Skool, instead of School.
