This is a 3A adjustable regulators using IC-LM350 that looks like LM317 Variable DC Power Supply, but high current higher 3A, adjust voltage 1.2V to 30V
All the high current power supply, adjustable voltage, current output
CAR Radio transmitters to use in home, need a ham radio power supply DC-12V or high current 13.8V power supply with enough power out of 5A - 30A. [...]
Simple 10A variable voltage regulator circuit diagram. Adjust output is 2V to 36V. Good idea that save. Using normal parts that you may store them.