RIGOL/ DG3101A has no output power

[azemati]

Hi everyone
In the Function generator DG-3101A,
Unfortunately, the output power has decreased 100 times
According to the picture of the IC whose number was deleted, I changed it and put LM7121 in its place, but it still does not work
Can someone give me a schematic of the amplitude part of this function generator?
Thank you for guiding me