26-08-2017, 11:21 AM
A variable frequency oscillator has been designed and simulated using the electronic workbench software multisim 8.0. It is designed between 20 KHz and 50 MHz using a colpitts oscillator configuration. The complete circuit is composed of a 2N3904 PNP transistor amplifier and two tank circuits that form the feedback network. The circuit was simulated and was found to range from 4.2MHz to 50MHz when the L2 inductor of 1μH at 360μH and from 20KHz to 4.8MHz when the inductor L1 ranged from 1.0μH to 1mH. The distortion analysis result for 20 KHz and 50 MHz shows a low distortion of 0% and 6% respectfully while the graphic view of the spectrum analyzer and the oscilloscope shows good stability, low noise and constant amplitude of oscillation.
An oscillator is the basic element of all AC signal sources and generates sinusoidal signals of known frequency and amplitude. It is one of the basic and useful instruments used in electrical and electronic measurement. Oscillators are used in many electronic circuits and systems that provide the central clock signal that controls the sequential operation of the entire system. The oscillators convert a DC input (voltage supply) into AC output (the waveform), which can have a wide range of different waveforms and frequencies that can be complex in nature or simple sinusoidal waves depending on the applications. Oscillators are also used in many pieces of test equipment that produce sinusoidal sinusoidal waves, square waves, sawtooth waves or triangular waveforms or simply a train of variable or constant width. LC oscillators are commonly used in radio frequency circuits because of good phase noise characteristics and ease of implementation. An oscillator is basically an amplifier with positive feedback or regenerative feedback (in phase) and one of the many problems in designing electronic circuits is to stop the oscillation amplifier when trying to get the oscillator to oscillate. The oscillator circuit is also used in the "exciter" section of a transmitter to generate the RF carrier. Other applications include their use as "clocks" in digital systems such as microcomputers, in the scanning circuits found in televisions and oscilloscopes. Oscillators are also used in teaching and research laboratories to produce signals and waveforms for specific applications. It also finds wide applications in the industries for the manufacture of many electronic instruments.
An oscillator is the basic element of all AC signal sources and generates sinusoidal signals of known frequency and amplitude. It is one of the basic and useful instruments used in electrical and electronic measurement. Oscillators are used in many electronic circuits and systems that provide the central clock signal that controls the sequential operation of the entire system. The oscillators convert a DC input (voltage supply) into AC output (the waveform), which can have a wide range of different waveforms and frequencies that can be complex in nature or simple sinusoidal waves depending on the applications. Oscillators are also used in many pieces of test equipment that produce sinusoidal sinusoidal waves, square waves, sawtooth waves or triangular waveforms or simply a train of variable or constant width. LC oscillators are commonly used in radio frequency circuits because of good phase noise characteristics and ease of implementation. An oscillator is basically an amplifier with positive feedback or regenerative feedback (in phase) and one of the many problems in designing electronic circuits is to stop the oscillation amplifier when trying to get the oscillator to oscillate. The oscillator circuit is also used in the "exciter" section of a transmitter to generate the RF carrier. Other applications include their use as "clocks" in digital systems such as microcomputers, in the scanning circuits found in televisions and oscilloscopes. Oscillators are also used in teaching and research laboratories to produce signals and waveforms for specific applications. It also finds wide applications in the industries for the manufacture of many electronic instruments.