I'm a hobbyist and I have 2 doubts regarding a power supply described into this schematic:
1) How do I differentiate a center-tapped power transformer from a non center-tapped one? My primary language is portuguese and I cant manage to translate it... Can I assume that "24V 2A" is a center-tapped transformer and "24+24 2A" it's not?
I need a +-20V power supply. Into the diagram, it recommends a 30V center-tapped or a 15+15V secondary in order to build one. But:
2) If I split a 30V center-tapped transformer, it will give me +-15V, not 20... Neither if I use a 15+15V, it will not amplify to 20V...