Question
Answer the following about one of the most practical circuit components, the oscillator, for 10 points each.
[10m] Stable oscillators have a feedback loop with loop gain magnitude equal to one according to a criterion named for this scientist. He also names an audible phenomenon caused by discrete jumps in ferromagnetic magnetization.
ANSWER: Heinrich Barkhausen [accept Barkhausen effect; accept Barkhausen noise; accept Barkhausen stability criterion]
[10h] A popular oscillator used in audio circuits is this one, which consists of a high band-pass filter and a low band-pass filter connected to an amplifier whose gain is slightly greater than 3 at the operating frequency.
ANSWER: Wien bridge oscillator [prompt on phase-shift oscillator]
[10e] Chaining together an odd number of these digital circuit elements in a feedback loop can be used to create a ring oscillator, which generates square waves. These digital logic gates output the opposite value of their inputs.
ANSWER: inverters [or NOT gates]
<Parameswaran, Physics>
Summary
| 2024 ESPN @ Brown | 04/06/2024 | Y | 1 | 0.00 | 0% | 0% | 0% |
| 2024 ESPN @ Cambridge | 04/06/2024 | Y | 1 | 10.00 | 100% | 0% | 0% |
| 2024 ESPN @ Chicago | 03/23/2024 | Y | 3 | 13.33 | 100% | 33% | 0% |
| 2024 ESPN @ Columbia | 03/23/2024 | Y | 5 | 14.00 | 100% | 40% | 0% |
| 2024 ESPN @ Duke | 03/23/2024 | Y | 1 | 20.00 | 100% | 100% | 0% |
| 2024 ESPN @ Online | 06/01/2024 | Y | 4 | 15.00 | 100% | 50% | 0% |
Data
| UNC A | UNC B | 10 | 0 | 10 | 20 |