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It could happen for real. The simulation program thinks the transistors, resistors and capacitors are exactly the same. Both transistors turn on at the same time. Then the circuit latches instead of oscillating.
You need to do something to make one transistor turn off for a moment to kick-start the oscillation.
Q2 in your second schematic is connected incorrectly.
Livewire should have an Initial Condition operator (component, etc.). In Spice, the command is
Code:
.ic v(b1)=0
which forces the voltage on the node named b1 to zero while the initial operating point is computed.
If you can set the initial condition of one of the bases to zero, the multivibrator will start.
You could also apply a short current pulse to almost any node to upset the equilibrium.
Did you pay money for that? I downloaded the demo. Mmmmm...
Linear Technology's SwitcherCAD III is totally free, and it is actually a serious Spice-based simulator. It does not have the toys (virtual instruments) that LiveWire has, but I believe it has a lot more capabilities in other areas. It is probably harder to learn to use if you don't have previous Spice experience, but there are several users here who know it pretty well, so you can get help if you need it.
Make the gains of the transistors, the values of the resistors and capacitors all slightly different, then it'll probably work.
Your simulation software looks pretty play school, it looks like an old version of Chrocadile Clips to me. I use the aforementioned but only for circuit diagrams; I don't normally rely on simulation software at all.
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