Unlike the previous circuit this one trigger when the temperature drops below the set value. The circuit is from June 1986 Radio Electronics magazine.
This source, found in a 1991 publication, was originally designed to operate with the CB18736E, an alarm...
We found this circuit in a publication of 1990. With the changes it can be mounted easily today....
This circuit mimics the sound of a siren when we turn the axis of the small DC motor. The...