Today we attempted to understand why the buzzer was working for a voltage of 3.55 instead of 12V. We found that the voltage across one the resistor in series with the electrolytic capacitor was different in our circuit than in Multisim. We found that the capacitor in out circuit was allowed to charge all the way up instead of 2/3 of the way that it should when connected in parallel to the timer. The resistor is supposed to drain some of the voltage across the resistor so that the capacitor is not charged up all the way. We also discovered that our buzzer will sound a square waves which is why it need the timer to produce the waves. But the timer only produces square waves at a Vcc of 3.55V. We are not sure why this is and next time we will try switching the timers.