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Typical NTC thermistors have 3.8% per degree at 20C, ten times the tempco of platinum. So put one of those in the upper arm of wheatstone bridge to do temperature compensation, sort of?

What we really want is to sustain constant delta-T relative to ambient air temperature, since that temperature difference is what drives heat flow and thermal equilibration

If we want resistance twice ambient, how hot is that? Around 180C! So: if we servo to constant resistance on hot wire, even if ambient changes by 20 degrees, delta-T between hot wire and air only goes from 160C to 180C, not a large difference.

We can just measure air temperature and correct for delta-T. 

 
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