Why does my oscilloscope display two frequencies

[Neukyhm]

Hi there, I have a Siglent oscilloscope and sometimes two different frequencies are shown. See the picture, it's the voltage at a Mosfet's gate (~111kHz) but it shows an extra frequency of 23.8kHz. What does this mean?

[ataradov]

One is coming from a hardware counter, the other one is measured by the software. On a noisy signal like this, they can be very different. Adjust your trigger point, and see if it makes any difference.

[tautech]

One is coming from a hardware counter, the other one is measured by the software. On a noisy signal like this, they can be very different.

This ^^

Adjust your trigger point, and see if it makes any difference.

It will !

Complex and/or noisy signals will give different readings so sanity checks of comparison to the graticules WRT timebase setting or using cursors can provide better and trusted results.