This simple 12 V power supply with current up to 2 A was found in a Popular Electronics from the 90s. The zener diode is 14 V and transistor Q2 can be a TIP42.
This circuit is indicated to operate from high impedance sources as piezoelectric transducers....
We found this circuit in a Motorola publication from the 70s. The circuit can be implemented with...
This double bench source has a fixed voltage output and an adjustable voltage output with current up...