Week 1 - 555 Timer Week 2 - The PCB Design Week 3 - Making Week 4 - Evaluation

Egg Timer 

  • Build It

      • You can now build your PCB, look at the pictures below and build your own PCB
      • Make sure you note the many different value resistors.


      • Remember, when soldering in the battery snap to go through the strain relief hole.


      • Lastly, plug in the 555 timer IC.

      • You can now test it.
      • Step 1. Turn on the switch
      • Step 2. Check the LED is on
      • Step 3. Select a time using the DIL switch
      • Step 4. press the reset button to start the time.
      • Check the time on a clock to make sure the delay time is correct.¬†
        • 2 mins = tooth brushing timer
        • 3 mins = soft boiled
        • 5 mins = medium
        • 10 mins = hard boiled

  • When the time is up, the other LED and the buzzer should turn on. You can either press 'reset' and start again, or turn the power off at the switch now.

Badge It


  • Upload photos of the front and back of your project.
  • Your solder joints are good, some dry joints or excess solder.
  • You component placement is good, a few of the components are off the board and not aligned correctly.