This circuit memorizes through an LED indicator if your phone was used during your absence. The circuit was found in a 90's EDN. Transistors are commonly used.
We found this circuit in an old publication on oscilloscopes. Its purpose is to observe the Ie /...
September 2017 - Panasonic Dy2L TVS diodes for network applications, security, medical equipment,...
This circuit was obtained in a Popular Electronics of the 90s. The circuit can be assembled with...