Electronics · Sensors and analog signals / Principles and inquiry
RC filters and frequency response experiment guide
Compare low-pass and high-pass filters using frequency response and input/output waveforms.
How does it work?
At cutoff both filters have magnitude 1/√2, approximately −3.01 dB.
Key relationship
fc = 1/(2πRC) · Hlp = 1/(1+jωRC) · Hhp = jωRC/(1+jωRC)
Try this investigation
- Compare low-pass and high-pass filters using frequency response and input/output waveforms.
- Run and record each of the three baseline presets.
- Compare the changed variable and its result with the baseline records.
Interpreting your results
What is the magnitude gain of low-pass and high-pass filters at cutoff?
About −3.01 dB
Assumptions and limitations
The elements are ideal and output is unloaded. Noise, parasitic effects and audio playback are excluded. Experiment on screen; do not reproduce this with real power supplies, outlets or high voltage.