This inexpensive variable power supply circuit with L200. The output current is up to 2A and the output voltage depends to the output voltage from transformer. VR 47R used for current adjustment and the VR10K used for output voltage adjustment.

This is regulated variable power supply circuit based on Transistor LM338. Short circuit protection added in this circuit.

Actually, this is ordinary regulated power supply, but the current expander using a transistor make this power supply become powerful.

Based on the datasheet, the stabilizer IC’s can deliver up to 1A output current. For example 78xx series regulators are available in different voltage ratings, but in any case the current should not exceed 1A.
The transistor [...]