I have built this circuit successfully on breadboard and simulated it in circuitlab (second and third image). Somehow the same circuit doesn't work. The output is supposed to be a sinusoidal signal with decreasing amplitude (third image). The output of the circuit below is the same pulse that triggers it. What am I missing?
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![Schematic_twin-t-w-pulse](//image.easyeda.com/pullimage/oCjmqXagvhQM1BzcBAxIbQT7vmz9k30NdyFUuTzI.png)
![twin_t.png](//image.easyeda.com/pullimage/P2C7DTQXKLG51VnniLstvU6OdUVCEL7HXwqCfpic.png)
![twin_t_plot.png](//image.easyeda.com/pullimage/6DsSAlPElU5GQWMzDR6s5VI5cCZ3cK8XmzoemH7l.png)
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