I find that when turning on my power supply I get waveform output for about half a second and then an instant cut off. I used a potentiometer as a voltage divider and it seems to work. (Turning the supply on and off again and listening to the pitch of the wave). I run the various circuits from a +/-12V supply with a third ground connection and have tried using TL072 and TL082 opamps but to no avail.
The Issue: When I build op-amp oscillator circuits (other than schmitt trigger oscillators which work perfectly every time) I find they need to be "jumpstarted" in order to start oscillating, I consistently encounter issues where turning the frequency too high permanently "turns the oscillator off", the oscillator slowly goes down in pitch only to stop outputting completely and the aforementioned issues.
The Question: Is there a common link/issue with op-amp circuits that cause these issues? When simulated, all the circuits output the correct waveform yet seem to be completely inoperable when actually built. Why does a schmitt trigger op-amp oscillator work perfectly every-time yet other don't? What do other oscillators (say a triangle/saw oscillator) rely on that a simple square wave relaxation oscillator does not?