The Colpitts oscillator is a time-tested design — from 1918. [The Offset Volt] has a few videos covering the design of these circuits including an op-amp and a transistor version.

In this walkthrough she demonstrates simulating a Colpitts oscillator using NI Multisim 14.3 – a deceptively simple analog circuit known for generating stable sine waves.

The Colpitts oscillator output is level-shifted using R4 and R5 to a zero of about 1.2 V, which is the microprocessor's analog comparator reference voltage.

2. Colpitts Oscillator Circuit: This includes inductors, capacitors, and a transistor to create the oscillating signal. 3. Speaker: To output the audible tone when metal is detected. 4.

Colpitts Oscillator: A type of oscillator that utilises a capacitive voltage divider and an inductor to produce stable oscillations, widely used for its simplicity and effective frequency control.