Found in American documentation, this switch is based on the 4093. The load will determine the supply voltage. The transistor is general purpose.
This circuit is from a 1998 Poptronics. The circuit triggers a buzzer after a certain time, waking...
An integrated circuit 741 (operational amplifier is the basis of this voltage indicator, which can also...
This transistorized voltage converter is one of the oldest that we find in technical publications. It...