Rigol DG5072 two channel function generator, ch1 attenuator fault

[Bjoern]

I got this waveform generator with a faulty attenuator at channel 1.
I can see the waveform with the correct frequency but also a DC offset.

I am trying to figure out why ch1 is not working properly.
The output transistor measure OK.

I am not sure which OPamp is the direct driver of the output transistors.
One of the 10pin SMD chips from Analog Devices is marked D 0M, i am not sure what that is
but I can measure a sine-wave on the working ch and none on ch1.

If someone could point me in the right direction would be very helpful.

Highly appreciated!

[Swainster]

Hi Bjoern,

I don't have any experience with this model AWG but my google fu says that 10 pin Analog devices IC is a digital potentiometer AD5243BRM10 - hope that helps a bit!

BTW, did I buy a Chroma DC load from you on Carousell, may be about a year ago? Can't be many Bjoerns in Singapore...

[Bjoern]

Hi, thanks for your help. I cant remember selling a DC load on Carousell but several other things so we might have met :-)