I'm a beginner to electronics. I just started to test transistors, but I've some doubts.
I've used this schematic to test a NPN 2N2222:
1 - How much Voltage or Amps should the base and the collector receive to pass current to the emitter? I can't figure out the math.
2 - With this setup, the LED when I don't have the button pressed have 1V current. I'm wasting energy? I can tunning this schematic to not wast any voltage when the button is not pressed?
Please give me some clues.