Now for an oscillator to work, we need an amplifier with a gain of greater than 1, and a phase shift of 360 degrees to get positive feedback.
First problem – the transistor was saturated, with Vc stuck near 0V. For an oscillator to start noise gets amplified, filtered by the crystal, amplified again etc. I reasoned that if the amplifier wasn’t biased to be linear, the oscillations couldn’t build up. So I reduced the collector resistor to 6.8k, and changed the the base bias resistor to 1.8M to get the collector voltage into a linear region. So now we have Vc=3.2V with a 5V supply.
Join us every Wednesday night at 8pm ET for Ask an Engineer!
Maker Business — How Authority and Decision-Making Differ Across Cultures
Wearables — Brightness know-how
Electronics — Tactile Confusion?
Biohacking — Eight Health Leaders Explain How The Medical Industry Could Be Changed
No comments yet.
Sorry, the comment form is closed at this time.