I really like ECE 123 course with Prof. Haller. The Professor who made us sing the Lehigh Alma Mater at the beginning of his class as I mentioned earlier in my blog. In his class, we are talking about operational amplifier and transfer functions. In ECE 081, we learned transfer functions. When we are giving a certain circuits, we need to calculate the transfer function (output voltage over input voltage), and draw graphs about its magnitude diagram and phase diagram. For yesterday’s homework from ECE 123, we are giving the magnitude, phase diagram and input voltage source to look for the output voltage. It was an interesting homework because it made us to think the problem in backward. In addition, that is how we figure about circuits in reality.