I do not understand your meaning by this ""Its because of the DC offset present on the sine/tria/square, is not present when the Select switch is open circuit.
""?!
As you can see from the earlier waveform plots, they swing about 6V, not 0V, so there is always a 6V or so DC offset.
From your earlier post I thought you were saying that the DC didnt work when the DC position was Selected, I must have misunderstood.
My Switch is always connected to one output of the waveforms and to the noniverting input of U8 via 100k resistor as shown in your modification.Actually I don't know why You added R9 in the circuit?
As my note above said, I thought that you had a problem with DC offset Select, thats why I added R9.
Can I experience 0 OFFSET by changing R21, and whats the Max of OFFSET I can expect by changing it?
R21 is a 50K variable, so that you can set the DC output offset.
Thanks like alway.