Here is the Problem. http://img577.imageshack.us/img577/3769/screenshot20110803at231.png [Broken] Uploaded with ImageShack.us I know the first part where the signal goes from A to B and i know what the signal will look like at B, as i used the inverting op amp formula. Vo=Vin x -Rf/R1 I understand from the image the op amp between A and B is an inverting op amp and which Resistor is which, Rf=100kOhms and R1=3kOhms. I worked Vout at B to be 0.4V so the signal drawn would just be the same shape as the signal above but drawn mirrored above the the 0V line and peak at 0.4V. The trouble is with the second part between B and C. I think the second op amp is a non-inverting op amp as the input from B goes into the + input of the op amp but i do not know how to calculate the output as the layout of the resistors and the use of a Capacitor are confusing me. Any help on this would be great as i feel i can understand it but the layout of the circuit is boggling my brain.