Try this free ebook http://www.ti.com.cn/cn/lit/an/slod006b/slod006b.pdf (section 15) If I have to guess you do not have enough gain in your circuit. Try to increase R2. It could also be some errors in your wiring of course. Check and double check everything even the component values
hi H,
If the Initial conditions are 'balanced' the sim will not oscillate, have you tried setting .IC= some voltage for an input on the leftmost OPA.? [initial unbalance]
The .IC= Vx is used in LTSpice, not sure if its the same for Spice.
E
This.
When I simulate oscillators, I set one of the supplies (assuming a dual supply) to ramp from 0 up to the desired voltage. It creates an initial imbalance that allows the circuit to start doing its thing.