24 - Signals with Multiple Frequency Components

 INTRO: Today we covered the topic of signals with multiple frequency components. In other words, this is something one would see when you have several input signals in your circuit. An example is if you were to have several different sinusoidal input signals feeding into your circuit, as opposed to the circuit we have been working with that just have one.

 Below Professor Mason did some examples of what we would be learning for the day.

Below we cover the topic of transfer functions. Voltage gain,current gain, etc., are all common function

 

LAB: SIGNALS WITH MULTIPLE FREQUENCY COMPONENTS

In today's lab we built a circuit with multiple input signals. Just like described above, this circuit has multiple frequency components. We will then measure circuit values across our circuit.

 Below is a picture of the circuit schematic that we will be building for this lab. We are building a low-pass filter, which will eliminate high-frequency signals from passing through it.

Below are some values we calculated for our circuit.


Below is a picture of our low-pass filter circuit that we built. Per the schematic 2 pictures above, we have two resistors and a capacitor in our relatively simple circuit.


For this circuit we apply a custom input wave. The wave is represented by the function: 20(sin(1000πt)+sin(2000πt)+sin(20,000πt)),  and then a sinusoidal sweep function.
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Here is our wave at 500HZ


 Here is our wave at 1000HZ
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Here is our wave at 10KHZ
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Here is the second part of our lab. As mentioned above, the second waveform that we run is a sweep function. Analyzing the wave, it can be seen that the blue wave gets more suppressed as time passes in the circuit.


CONCLUSION
In today's lab we dealt with circuits with multiple frequency components. The frequency response of a circuit is is the variation in its' behavior with a varying input signal frequency. We also discussed transfer functions and some common types that we have already used through this course. At times like these I reminisce about my time in the enchanted land of Fantastica. My main questions arising out of the completion of this lab is why didn't Bastian take the Rock Monster to fight the Darkness? Why did Atreyu take Artax through the Swamp of Sadness when he CLEARLY could have taken him over the forest of Fantasies!? I took this class in hopes that these questions would be answered, but alas, I must extend my search further to answer these pertinent life questions.