EXPERIMENT7:SIGNAL PROCESSING AND OSCILLATORS.
To construct and test various oscillators and waveform generators.
To stimulate and build various operational amplifier circuits and to verify the operation.
To note the varying signal processing capabilities possible from op-amp circuits.
Anoscillatorisa gadget thatproduces consecutive signals of electrons from one point to anotherto pass a message. They are mainly in form of sine or signal wave. Theirpurpose is to convert DC current to AC current for electronic devicesor input. There are two types of oscillators. This are Relaxation(nonlinear) and Harmonic(linear) oscillators.
Therelaxation oscillator is the one that produces triangular or squaretype waves. The difference in the types of waves is because a numberof them are used for different reason. For instance, the square wavesare used for timers and counters. Various types of nonlinearoscillators include ring, delay line, multivibrator, royer and rotarytravel oscillators.
Theharmonic oscillator is the one that transmit electrons inform offrequency to an amplifier to produce an electron noise. There are twotypes of linear oscillator. These are feedback and negativeresistance oscillators. The difference is that the feedbackoscillator produces a positive feedback while the negative resistanceproduces a positive feedback.
Signalprocessing is how the waves either harmonic or relaxation oscillatortransmit the electrons from one point to another.
Circuitwith 2Vp,1kHz sine, Triangle and square wave inputs
Enterthe circuit to SPICE (and ALWAYS provide the SPICE circuit withdiagrams)
Determinethe oscillation frequency and compare to the expected value
Recordall waveforms available from the circuit
Simulatethe circuit with 2Vp 1kHz sine triangle and square wave input
Obtainthe Bode plots and determine: the shape of the filter the centrefrequency the -3dB roll off frequency and the pass band gain
Obtainthe DC transfer characteristics of this circuit and verify that thecircuit is performing full wave rectification.
Explainwhere this circuit would be used over the alternating diode bridgerectifier or over the alternative difference Amplifier.
Record both values of the current and voltage by opening the ‘PSpice Design Manager. Enter all the data required as to per your personal finding. The placed components will beautomatically assigned a default initial value.
AC voltage is got by dividing the voltage output over the voltage input.
ACvoltage = 15/15 = 1 but since the voltage out is more than the voltage so we ignore the negative sign.
PSpice is automatically set up for DC analysis. Biasvoltage isan electrical charge used in transistors. It causes substances to beconductive. Amount of current passed through a conductor is similar to the bias voltage applied . Voltage can either beforward bias or backward bias. Vacuum tubes can also be used tocontrol bias voltage.
Filter types are used to select certain band of signal frequencies. They are used in radio communications. They have bothresponses of high pass and low pass. High pass is where high signals are passed while those low are blocked and vice versa.
A quick way to determine the position of the horizontal asymptote ofa
Rational function (having no common factors) is withthefollowing method.
Look atthehighestorderdegreeinthe numeratorand thedenominator,
If thehighestdegreeisinthedenominator,thenthe horizontalasymptote
If the highest degree is in both the numerator and denominator, then the
horizontal asymptote is the ratio of the coefficient of this highest term in the numerator and denominator.
If the highest degree is none degree larger than the highest degree in the
Denominator,then the function has aslant asymptote. By this, one is able to obtain the value ofthe voltage and current from the graphs.
Bridgevoltage formulaV =[[R4 /[R3 +R4]]– [R2 /[R1 +R2]]]* VTotalresistance is given by:RE =[[R1 +R2]* [R3 +R4]]/ [R1 +R2 +R3 +R4].
Fromthe MicroSim Probe graph:
The maximum power to the load is got by taking the furthest point the line graph touches at the x-axis. While the maximum power of the available at the load resistor is got by recording the highest point on the y-axis
The function of the circuit is to enhance equal and smooth flow of electricity in order to avoid any form of short circuit.
The load reduces the voltage output by restricting the flow of current.
Sucha circuit would be used motors or electrical devices.
Thecircuit achieves this by clamping. They are preferred mostly by people since they are safe and economical to maintain.
Itcan be concluded that oscillators and signal processors have been avital advancement in the current growing world.
Ithas lead up to innovation advanced technology that has enabledprocessing and interpretation of spoken words, production ofelectrical signal that represent sound, analyzing of financial datausing signal processing techniques and analyzing extractedinformation from signal television and radio transmitter are examplesof signals generated by oscillators etc.
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Snelgrove,Martin (2011 Oscillators. McGraw-HillEncyclopedia of Science andTechnology,10th Ed., Science Access online service.McGraw-Hill.Retrieved March 1, 2012.