hey everyone currently I've got a project which consists of three different circuits. first one is a signal generator, second one is a waveform selector and the last one is filter rectifier and all of them will be connected together. all three circuits schematics has been attached here which u can take a look at. the point is that our lecturer wants the description and the objectives of each circuit which I cannot understand what they actually do except their title. I mean the signal generator is sending signals to the waveform selector and it forms the signal to 4 different shapes (sine, triangle, sawthooth and square) and then the last circuit will rectify the signal?? is that correct or I don't see other objectives of the circuits?
thanks in advance.

 

Your 555 chip is a Square wave oscillator, feeding into a Wave shaper transistor which produces the Sawtooth and Sinewaves, then fed into an op amp for boosting the signal.