A Bandwidth limit reduces unwanted waveform noise.
You can apply a Bandwidth limit to any channel of a PicoScope 4x25 or 4x25A Automotive oscilloscope. The limit is fixed at 20 kHz. This means any parts of your measured signal that have a frequency above the limit will be reduced in amplitude. And the higher their frequency above the bandwidth limit, the greater the reduction.
Bandwidth limiting is also referred to as hardware or analog filtering.
Every waveform you ever capture will consist of multiple frequencies. Both the waveform of interest and the measurement noise contribute to those frequencies. When your waveform of interest is known to consist of frequencies less than 20 kHz, you can apply a Bandwidth limit to reduce the remaining high-frequency oscillations due to noise. This cleans up (filters) your waveforms so you can clearly view and analyse them on screen.
As a Bandwidth limit is applied before your measurement is digitised, there is no resulting Digital Signal Processing (DSP) delay before you see the waveform on your screen. For this reason, it is convenient to use a Bandwidth limit, rather than DSP filtering, where the waveform characteristics allow.
Open the Channel options panel for the desired channel and, under Bandwidth Limit, select the 20 kHz option.