I am very new to the concept of Wien's bridge and am trying to make a basic circuit of it but didnt get the expected output (noise only).Tried to simulate on Multisim but got the same output.I have gone through many documents on the web but they are either too technical or incomplete.
Here is my circuit:
I believe since both my attempts gave me the same output I must be doing some mistake. Also I have problems understanding the concept of gain, why it should be slightly greater than 3 and the requirement of initial noise for the circuit to work.
Can someone please help me out.Any help is greatly appreciated.Thanks
I made a couple of changes in the circuit and it was working well enough.
First of all, I changed the OPAMP from "AJ741JN" to "741". Second I added an extra R5 (22k) resistance to the circuit and changed the connection from pin 2 (see new figure).
After making these changes the circuit starts to produce a signal of 50 Hz frequency but the wave form is a distorted sine wave. Adding a couple of "1N4007G" diodes as shown eliminates this problem as well (dont know how).