Week 0 - Soldering Exercise

Soldering is fun, but I didn’t understand everything on the circuit yet:

  • What does a transistor do?
  • Why is the refresh rate necessary?
  • Are the resistors necessary to not burn out the LEDs?
  • Is the resistance of the five through-board resistors 160 Ohms 5%? (Used this calculator)
  • How can I calculate the correct resistance given that the input voltage is 9V DC.