Hello friends. This is my first post to this forum, thanks for having me and forgive me if I posted to the wrong place, feel free to move it if necessary.
According to the datasheet (https://datasheetspdf.com/pdf/789898/EGmicro/EGS002/1) paragraph 4. Testing, one should obtain patterns like those in attached EGS002 scope test figure.
I also attached two scope traces that resembles what was expected but not so close. I used a 4.9k resistor instead of a 5.1k and a 108nF capacitor instead of 100nF recommended.
Can those deviations produce all that distortion? Have you done this tests with your boards? Should I buy another board or proceed with this one?

 

Very likely your scope probes are not calibrated.

I used a 4.9k resistor instead of a 5.1k and a 108nF capacitor instead of 100nF recommended.

I can not read the data sheet. What resistor and capacitor?
I need to know how the scope is connected to the EGS002.

 

Very likely your scope probes are not calibrated.

I can not read the data sheet. What resistor and capacitor?
I need to know how the scope is connected to the EGS002.

Thank you @ronsimpson for your kind reply. I apologize for the Chinese link, please try the following ones:
http://www.mkpochtoi.ru/EGS002_manual_en.pdf
https://content.instructables.com/ORIG/FOB/OO44/KGXP6I91/FOBOO44KGXP6I91.pdf

I hope those links lead you to the ASIC manual, where you'll find the chapter 4 about Testing. Regarding the probes, they show perfect square waves when connected to my scope internal test oscillator, so I guess they are ok.

Looking forward to your advise, once more I'm sorry by the wrong link.

 

On your scope there is a place labeled "cal 1V". Put the scope on that point and send picture.

 

Your scope is wrongly set to AC. Instead it should be set to DC.