We found this circuit in a 1980s documentation. Equivalent components can be used. The circuit senses temperatures in the range of 0 to 50º C and uses a transistor as sensor.
With this luminous remote control, which we found in a 1990 publication, using a flashlight you...
We found this circuit in a 1967 Electronics World. The circuit can be designed to control other...
This circuit can be used in a signal level indicator with LEDs. The circuit is from an Electronics Now...