Awhile back I published a simple design idea for a thermal airspeed sensor based on a self-heated Darlington transistor pair. The resulting sensor is simple, sensitive, and solid-state, but suffers ...

A recent Design Idea presents a circuit to measure an airflow rate up to 2000 fpm using two transistors in a Darlington configuration. One transistor works as a self-heated thermal sensor and the ...

Supply flow into an occupied space is generally a mixture of return air and fresh outdoor air that has been filtered and then conditioned through heating or cooling coils. This volume of supply air ...