This powerful pushbutton uses a power MOSFET. We found it in a Popular Electronics magazine from the 90s. The MOSFET must be mounted on a heat sink.
This circuit is from an American documentation from the 70's using transistors of general use of...
This circuit is intended for PWM speed control of a motor up to 500mA, using integrated circuit 555....
We found this circuit in a 1983 English magazine, but it can be easily assembled with the BC548...