This stabilized source can supply currents up to 700 mA and the output voltage is close to 15 V. a little less with the load. The power transistor must have a good heat radiator.
This circuit was found in an English operational documentation from 1970. The circuit can be...
This circuit is from a 1974 publication. It generates a pulse with several sinusoidal cycles from...
This solar cell driven circuit makes 4 LEDs run at a speed given by capacitor C2. The circuit is...