This is 5 Volt Linear power supply regulator circuit. It uses electronics part that seek easily have no zener diode , and the integrated circuit use Transistor 2N3055 and other. Which seek easily use diode perform heal voltage be stable. By diode 1N914 number uses 1N4148 number can replace. For Transistor 2N3417 use the number BD139 equiv get. If use Transformer 1-2A circuit be this size give current get about 1 Amp. Friends may don’t be bored with line this circuit. I thinks it may advantage seek part easy and economize good yes.