Day 27 Filters (NO LAB, last class)

We started the day with talking about resonant circuits and filters. We talked about all the different type of filters. Low pass, High pass, Band pass, and Band Stop. We were asked to come to the conclusion for omega.

White board work for finding omega. There is a linear point if which omega is best for outputs.

There are to types of resonate circuits, series and parallel. We were asked to do an example of a series circuit.

White board work of the series circuit. Transform to phasor, use the omega equations, and Band pass = w2-w1 and Q = omega not Wo/B.

We were then asked to try a parallel resonate frequency circuit. For parallel circuit everything is the same except of the omega function. Th omega functions is 1/over. Wo is the same, and band pass is the same, and Q is found the same.

White board work of the example tried in class, be sure to use the right omega equations.

We were then asked to work the problem another way around and design a circuit to find a specific Q.

White board of designing a circuit that would produce a Q with given numbers.

Lastly we had a deep conversion about GPA.

White board work of the limit of GPA as it approaches zero.

lastly we did an example of a band stop filter. We did the work and use jw = S, and then found the transfer function of Vout/Vin.

White board work of a band pass filter. S = jw, find roots.

In  summary the last class covered filters. There are two types resonant series and parallel resonant circuits. Both use the same equations except parallel has the 1/over relations for omega. We talked about low pass filters pass low frequencies and stops high frequencies. High pass filter pass high frequencies and stops low frequency. Band-pass filter passes frequencies within the frequency band and stops all other frequencies. Band-stop filter passes frequencies out a frequency band and stops frequencies within the frequency band. We did examples of passive series and parallel resonant circuits, and then a version where we design a circuit to get a Q factor. Q factor is how selective a circuit is for a frequency. And the band with is w2-w1.