I'd like to hear your opinion since according to the support answer form the RIGOL authorized dealer this topic is closed. I bought a new MS01074Z-S about 14 months ago. During this time it was used frequently and it wasn't abused in any sense (e.g. overvoltage on inputs, no AC mains surges, mechanical pressure on probes and input BNC connectors, etc.). Recently I noticed that something is wrong when no signal is present on any of its 4 inputs. At first I thought that probes are picking up some external noise, but even without probes and when I selected input grounding the situation was not improved a bit. Here is the screenshot with all inputs
grounded before I contact their dealer technical support:
Technical support suggest me self-calibration. I follow that and self-calibration begins. After lots of clicking and traces moving around the calibration is successfully finished. After restart I got the following (again all input are grounded):
It seems like an improvement but just selecting the AC coupling even without probe cable connected I got the following on the Ch3 that looks better then others on the above picture:
I sent the same screenshot to the dealer and I got the following response:
... Rigol compared it to their own devices and with the device specifications, this noise is considered normal and within specs for the MSO1000Z series devices. Unfortunately we can't improve it any more.
With different time base grounded ch3 looks like this:
My question is does anybody experienced the same behavior on not completely new MSO or any other RIGOL's device from the same series/class? Thanks in advance.