The starting pulse is generated by the positive power supply’s startup slope. If the power supply does not slew fast enough the oscillator will not start. R3 can be increased to increase the gain and likelihood of starting. It also increases distortion when the amplitude as the peaks aproach the power supply rails. (Circuit is created by John Bishop based on a design by Neil P. Albaugh.)
1 kHz Wien-Bridge Oscillator circuit:
Online Simulation of the “1 kHz Wien-Bridge Oscillator” Circuit
The great feature of the TINA circuit simulator that you can analyze this circuit immediately with TINACloud the online version of TINA. Of course you can also run this circuit in the off-line version of TINA.
You can send this link to any TINACloud customers and they can immediatelly load it by a single click and then run using TINACloud.