Based on a 555, this 80's American documentation circuit detects the voltage of a battery and can then disconnect the charger. The transistor may be a general purpose type.
This effects circuit can be used with microphones or guitars. The circuit is from an American...
We find this circuit in a Popular Electronics of the 90s. The circuit is passive and the coils...
The purpose of the circuit shown in the figure is to open and close the contacts of a relay...