Rigol oscilloscope Repair

[Chess]

Hi,guys i'm working on a DS1052E Oscilloscope
the problem is that any DC signal applied to the input of the scope is inverted eg:if i put 5 Volts DC than the scope displays a -5 Volt DC signal.I have done a fuctional checks on the other functions and it's all good it's just this one problem,don't have a service manual to start with.Can anyone help me on this.Were should i start,probaly from the input

[Radio Fox]

Re: Rigol oscilloscope Repair

I don't have one of these scopes myself, but does it pass the self-cal tests?

You don't have any of the options set to "invert" do you?

[rievax_60]

Re: Rigol oscilloscope Repair

Hi,guys i'm working on a DS1052E Oscilloscope
the problem is that any DC signal applied to the input of the scope is inverted eg:if i put 5 Volts DC than the scope displays a -5 Volt DC signal.I have done a fuctional checks on the other functions and it's all good it's just this one problem,don't have a service manual to start with.Can anyone help me on this.Were should i start,probaly from the input

Have you checked the invert function?

[ben7]

Re: Rigol oscilloscope Repair

Tried different test leads? Did it have this problem out of the box? Just want to be sure all these things are good, lol

[Chess]

Re: Rigol oscilloscope Repair

It does a self test upon powering up,but i did not check to see if there is any inverting function switched on but i doubt.Is there an inverting function on Rigol scopes with this model?Any way I've all ready open the scope up i'm going to check the inputs and the attenuation box of the 2 inputs.Any help would be appreciated

[Kiriakos GR]

Re: Rigol oscilloscope Repair

It is pointless even to visually inspect the PCB, when the same thing happens in both channels.
From the other hand, you have not mention any firmware revision ? Or if the scope has been fall in a hand of a trainee wizard who played with it firmware.

Call RIGOL and send it for general check or repair.

[kc8adu]

Re: Rigol oscilloscope Repair

sounds like some sort of setting issue.like a function to invert a channel with respect to the other.
silly to send it back to the mothership over something like this.
time to RTFM.

[Chess]

Re: Rigol oscilloscope Repair

Ok,Im gonna close it up and check all of these small things again just to make sure,i do have another scope but its's just that it's also faulty Coupling function messed up but that's a story for another day.Thanks for the help guys much appreciated.

[Radio Fox]

Re: Rigol oscilloscope Repair

It does a self test upon powering up,but i did not check to see if there is any inverting function switched on but i doubt.Is there an inverting function on Rigol scopes with this model?Any way I've all ready open the scope up i'm going to check the inputs and the attenuation box of the 2 inputs.Any help would be appreciated

Most (if not all) modern scopes have an invert function. It would have been the first thing I would have checked considering the effect you are seeing.

The user manual tells you where to find it.

I don't know if the self test does the same thing at switch-on, but the menu also has a self-cal function. Have you tried this?

You could also try using the "Auto" mode while applying the signal. This will switch off the invert function.