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What is the electrical dual of Colpitts oscillator?
A Colpitts oscillator is the electrical dual of a Hartley oscillator. The feedback needed for oscillation is taken from a voltage divider made of two capacitors, whereas in the Hartley oscillator the feedback is taken from a voltage divider made of two inductors (or a single, tapped inductor).
How does the Colpitts oscillator work in the LC tank?
First case: The Colpitts oscillator is sort of a reverse on the Hartley oscillator. Instead of a tapped coil, it uses two capacitors in series to provide the feedback point. Because feedback is through the capacitive leg of the LC tank circuit, the total capacitance of this leg is the series combination of C1 and C2, so that C = (C1*C2)/ (C1+C2).
How are Colpitts oscillators similar to shunt fed Hartley circuit?
Colpitts oscillators are somewhat similar to the shunt fed Hartley circuit except the Colpitts oscillator, instead of having a tapped inductor, utilises two series capacitors in its LC circuit. With the Colpitts oscillator the connection between these two capacitors is used as the centre tap for the circuit. WWW.ELECTRONICS-TUTORIALS.COM
How is the frequency of a Colpitts oscillator determined?
The frequency of the oscillations are determined by the value of the capacitors and inductor in the tank circuit. Thus the main difference between a Colpitts Oscillator and a Hartley Oscillator is that the former uses tapped capacitance, while the latter uses tapped inductance. What are the advantages and disadvantages of Colpitts oscillator?
How is the Colpitts tank similar to the Hartley tank?
Common Base Colpitts Oscillator. This circuit is very similar in operation to the Hartley oscillator described in Oscillators Module 2.1 but the Colpitts LC tank circuit consists of a single inductor and two capacitors. The capacitors form in effect, a single ‘tapped’ capacitor instead of the tapped inductor used in the Hartley.