This circuit was found in a 80s American documentation. The zener diodes determine the points of action of each stage and the transistors can be general purpose types.
This small power supply is suitable for powering devices using 9V batteries. The circuit uses...
Found in a 90s Silicon Chip documentation, this circuit provides a current of 3 A and the voltages...
This sensor triggers an oscillator emitting sound when a magnet is approached by a reed switch....