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Amith2006
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Why does Hartley Oscillator produce a sine wave?Is it just because Barkhausen condition is satisfied?
antoker said:waht: are you sure about 360? ;) You're required to get a 180 degree phase shift in your feedback loop in order to be able to sustain oscillation at a particular frequency. Start up kick is not produced by a noise, but by an initial transition between zero volts and up to a Vcc level(resulting in step in inductor loop), which produces a transient in a feedback circuit allowing the circuit to start oscillation and continue to "chase its own tail"
antoker said:P.S take a look at the png file attached, voltage is measured between the input/output of a feedback circuit in simple transistor circuit.
antoker said:P.P.S Sometimes designers add a "tank circuit" to a already stable oscillator in order to use it as a Band-Pass filter, since oscillators tends to produce a lot of unnecessary harmonics.
How much noise are we talking about here? I would really like to see an oscillator with 0V Vcc being started & sustained by some random noise in the system. Again, my bad english tends to create misunderstanding.Oscillators most certainly can be started by noise in the circuit.
Yep, shows 180 degree phase shift like you said. Says nothing about the amplifier being an inverting amp.
Averagesupernova: I think you misunderstood me, when I was talking about oscillator as a BP-filter, what intended to say was: Since, oscillators tend to produce more harmonics, tank circuits are introduced on collector side of transistor in order to clean up the signal.
Oscillators most certainly can be started by noise in the circuit.
How much noise are we talking about here? I would really like to see an oscillator with 0V Vcc being started & sustained by some random noise in the system. Again, my bad english tends to create misunderstanding.
Yes, I was referring to 180 shift between the input/output network, I wasn't talking about the whole transistor stage
If you power up an oscillator and then stop it by loading the inductor or some other subtle means, some oscillators can start on their own simply due to thermal noise.
A Hartley Oscillator is an electronic circuit used to generate a high-frequency sinusoidal waveform. It consists of a tuned circuit (usually an inductor and capacitor) connected to an amplifying device (such as a transistor or operational amplifier). The oscillation is produced by the feedback between the tuned circuit and the amplifier, which results in a continuous sine wave output.
The main components of a Hartley Oscillator include a tuned circuit, an amplifying device, and a power supply. The tuned circuit is usually made up of an inductor and a capacitor, and it determines the frequency of the output waveform. The amplifying device is responsible for providing the necessary gain for the circuit to sustain oscillation. The power supply provides the necessary voltage for the circuit to function.
The tuned circuit in a Hartley Oscillator works by storing and releasing energy in the form of an alternating current. When the circuit is tuned to its resonant frequency, the inductor and capacitor will alternate between storing and releasing energy. This results in a continuous oscillation or vibration, which produces the desired sine wave output.
Feedback is crucial in a Hartley Oscillator as it is responsible for sustaining the oscillation in the circuit. The feedback occurs when a portion of the output waveform is fed back into the input of the amplifier. This creates a continuous loop that keeps the circuit oscillating at its resonant frequency.
One of the main advantages of using a Hartley Oscillator is its simplicity. It requires only a few components and can be easily constructed. Additionally, it produces a pure sine wave output, which is essential in many electronic applications. It is also highly stable and can maintain a constant frequency over a wide range of operating conditions.