Author Topic: Strange behaviour of RIGOL DS1054z  (Read 284 times)

0 Members and 1 Guest are viewing this topic.

Offline Windows9Professional

  • Contributor
  • Posts: 20
  • Country: at
Strange behaviour of RIGOL DS1054z
« on: February 18, 2020, 05:02:58 pm »
So I've used my DS1054z intensively in the last few days since I wanted to calibrate a shunt sense resistor and today I've noticed a very strange behaviour of my scope:

Every time the scope switches from 500mV/div to 200mV/div (with 1X attenuation) I hear a relay switch, which is pretty normal. The strange things start when you switch into 200mV/div:

!Some! fast changes in voltage result in capacitor charging curves/slopes, which completely dissapear when switching to higher voltages/div.
These are visual in picture 1

This does not happen with 10X probe attenuation


I wanted to add an negative offset to the waveform as seen in picture 1 to get a better view on the charging slopes, but as I turned the offset knob on my scope, the curves disappeared (picture 2). They seem to vanish proportional to the offset I add. I cant imagine how this happened, since I always thought the offset knob was just a software adjustment that basically slides the waveform up and down the screen.

I figured all of this out, when I was scoping a 50% duty cycle pwm signal from my atmega8 (picture 3)

So does somebody have an idea if my scope is broken, or if this is just an effect of an 1X probe?

Note: When I turn off the output of my lab power supply, the charging curves disappear, while my signal gets shown without a problem for half a second (till the internal caps of my supply have discharged), so is this some kind of ground loop problem? (my PSU is linear & has an isolated output)

Picture 1: https://ibb.co/72kp79Y
Picture 2: https://ibb.co/pZPF8L5
Picture 3: https://ibb.co/vZ48PCX


« Last Edit: February 18, 2020, 05:14:25 pm by Windows9Professional »
 

Offline StillTrying

  • Super Contributor
  • ***
  • Posts: 2535
  • Country: dk
  • Country: Broken Britain
Re: Strange behaviour of RIGOL DS1054z
« Reply #1 on: February 18, 2020, 06:28:29 pm »
!Some! fast changes in voltage result in capacitor charging curves/slopes, which completely disappear when switching to higher voltages/div.

When you've got a lot of the waveform well off the screen it's quite normal to see some strange curves when the waveform reappears on the screen, it's just the analogue amp parts recovering from the overload.

Here's a Siglent example I remembered.
www.eevblog.com/forum/testgear/siglent-sds1000x-series-oscilloscopes/msg1208426/#msg1208426

Quote
This does not happen with 10X probe attenuation

That works as well, same thread.
www.eevblog.com/forum/testgear/siglent-sds1000x-series-oscilloscopes/msg1210522/#msg1210522

A Rigol one.
www.eevblog.com/forum/testgear/rigol-ds1054z-vertical-distortion-problem/

So I don't think it's broken.
CML+  That took much longer than I thought it would.
 

Offline Windows9Professional

  • Contributor
  • Posts: 20
  • Country: at
Re: Strange behaviour of RIGOL DS1054z
« Reply #2 on: February 18, 2020, 07:14:19 pm »
Thanks, im pleased to hear that I didn't break my scope
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf