We found this circuit in the March 1999 issue of Electronics Now magazine. The indicator used is an analog type. The values indicated depend on the calibration.
In this circuit, which uses one of the four comparators of an LM339 (or LM139 or 239), capacitor C1 and...
This timer activates a relay after a time interval of up to 15 minutes has elapsed, starting from...
This inverter can reach a power of 300 W depending on the transformer used. In this case, a...