Starting from scratch, this video shows how to build an RC low pass filter in the QUCS circuit simulator, including schematics, simulation, equations, and plots.
The RC low pass filter frequency domain response, shown in this video, is discussed in detail in my book “First and Second Order Circuits and Equations – Technical Background and Insights”. Published by John Wiley & Sons, Inc., the book “First and Second Order Circuits and Equations”, (called “1st & 2nd” for short) is available here:
https://www.wiley.com/en-us/First+and+Second+Order+Circuits+and+Equations%3A+Technical+Background+and+Insights-p-9781119913535
Section 6.4 of “1st & 2nd” provides a detailed steady state frequency domain analysis this exact RC low pass filter circuit. In addition, there are other sections covering series high-pass RC, series RL, and parallel first order circuits’ frequency domain behavior.
For a video on the circuit theory of the series RC low pass filter, please see this companion video:
“RC Low Pass Filter Electronics Tutorial, please see my video:
https://youtu.be/iXrfQfknlBU?feature=shared