Colpitts Oscillator

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Colpitts Oscillator

• Ruba Sbaih
• Jeelan ataree
• Supervisor
• Prof Marwan Mahmod

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Background

• An oscillator is a circuit that outputs a
  repetitive electronic signal i.e. a sine wave.
• The Colpitts oscillator is known for using a
  capacitor voltage divider as its feedback source
• Advantages include
• Frequency stability.
• A simple and robust design.

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Background

• For oscillation to occur the Barkhausen criteria
  must be met.
• Loop Gain
• Phase Shift must equal zero
• Magnitude equal to unity
• Realistically the magnitude will be greater than
  1
• Determine if criteria is satisfied by checking
  the loop gain at the frequency of oscillation

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Goals

• Design a Colpitts oscillator using and using it
  for lighting the fluorescent lamp.
• Build and test design
• Obtain frequency of oscillation
• Output a non-distorted sine wave from
  self-oscillation

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Design
Neon light
PV
Colpitts oscillator
Neon light
Colpitts oscillator
12v
Neon light
Colpitts oscillator
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Practical Colpitts Oscillator Circuits 

• We tried three circuit for the colpitts
  oscillator
• First

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• Second

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• And the third one

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• This is the output signal
• By noting the of squares
• We found that the
• Frequency is 9KHZ
• and the output voltage
• 200 v

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Correction the power factor

• By installing suitably sized switched capacitors
  into the circuit, the Power Factor is improved
  and the value becomes nearer to 1 thus minimising
  wasted energy and improving the efficiency of a
  plant.

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THE COST

• The colpitt oscillator does not expensive because
  its circuit very simple and required only a
  single transistor free And when we use the PV
  cell to supply the power to the oscillator we
  will not need any type of power supply to play
  it.