Using a Colpitts oscillator, I would like to try to detect a letter thrown into a mailbox. For the detection I use C1 and C2 created on the PCB as copper areas. I assume this would slightly change the oscillator frequency 100 kHz temporary which I will measure by the Microchip ATtiny202 MCU. The Vcc is 3.3 Volts. How to fine tune the components values to get smooth oscillations? I can set the ATtiny202 analog comparator to 0.55, 1.1, 1.5 (default value) or 2.5 Volts.
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