Continued feedback lab2

- Note that the phase margin is based on observing the LOOP gain!!! Here we only see the total system's (closed loop) gain and it is not really easy to identify the loop. So looking at phase shift and unity gain frequency of the total system does not give you clear clues on where the phase shift and unity gain frequency of the LOOP may be. Check figure 5.20 for an illustration that the two behave differently. It displays Aol and Acl. The Phase of Aol is the same as the lopop gains (if beta has no frequency dependency), and the frequency where Aol becomes 1/beta is the unity gain frequency of the loop.