Scanning encoder debounce on new scope

[richard]

But there is still some static that cycles through at a regular rhythm. Here it is at a slower rate so it's more apparent:

would your mains power be at 60Hz ?
hint 16.667mS

the A B debounce looks very uneven between rising and falling edges. the unequal phase shifts so introduced will make R.E data interpretation interesting, especially at varying rotational speeds

[Ioannis]

Do you have any Switch Mode Power Supplies, either 5Volts or other?

The noise might be because of that. If it is on a specific pattern and rate then something else cause this. Either clock, interrupt or as you said USB action.

Critical decoupling may come to rescue. Also earthing correctly also may help.

Ioannis

[Demon]

ARGH.... I finally found out what is that regular noise, the probes reset to AC coupling. I haven't looked in the manual yet if there's a way to save the current setting as Default.




About the uneven edge spacing, it's mostly the A wiper (yellow) that varies a LOT. B wiper seems to remain stable on average (sometimes it gives a longer intermission, but nothing as radical as A wiper).

I don't know if it's me that damaged the rotary encoder, or if it's "cheap" that way. I turned it countless times both directions, and I don't find a pattern.

If I turn CW and get a long intermission, I turned 2 clicks CCW, then turned again CW, but didn't get the long intermissions again.

[Demon]

I moved the posts here from the SDS-1104 review thread.

Your waveforms seem to indicate that you might benefit from adjusting the trimmer capacitor on your probe(s).

Yup, waveforms are cleaner now.