~Day 9~

After what had happened yesterday, I spent 3 hours to reconstruct our circuit and make it neater. It did not turn out well when I tested with the 9V battery.Only one LED lighted up. I decided to bring it to class and discuss with Shahirah.

Apparently, it was our 555 timer that caused the problem. We changed the IC and the circuit is finally working!!
However, the time delay was fast. The question requested it to have a short pause of 3 seconds. But we are having less than 1 second's delay.
We googled up and finally found  the way to solve, it was the resistors and capacitor as shown below that control the delay.  555 timers

After several trials, we changed the values of both R1 and R2 to 100kohms and C to 10microA. Finally we got the desired result.