This circuit was found in an Electronics Now from the 90's. The integrated regulator circuit and the power transistor must be equipped with heat radiators.
September 2017 - SparkFun offers through Mouser Electronics its protboard solderless board that...
A low frequency divider can be made using common unijunction transistors as shown by the figure...
June 2016 - Mouser can immediately deliver the TPS54xx plate for experiments with Buck converters from...