1. An Armstrong oscillator has M = 0.1 μH and L = 3.3 μH. What is the feedback fraction? What is the minimum voltage gain needed to start the oscillations?
2. A crystal has a fundamental frequency of 5 MHz. What is the approximate value of the fi rst overtone frequency? The second overtone? The third?
3. A crystal has a thickness of t. If you reduce t by 1 percent, what happens to the frequency?