Simulating (absolutely) symmetrical circuits

[Harald Kapp]

Harald Kapp submitted a new resource:

Simulating (absolutely) symmetrical circuits - Ideal components lead to unexpected simulation results

Other than a real circuit, SPICE deals with ideal components. In a completely symmetrical circuit this may lead to unexpected behavior. For example a simple astable multivibrator may not vibrate at all but assume a stable state. The circuit in figure 2.10-1 simulates a stable 39.7 mV on the out-pin without any tendency to oscillate at all.
Figure 2.10-1 symmetrical astable multivibrator is stable
You may force SPICE to assume a defined initial state for the simulation using the .IC directive...

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[(*steve*)]

I would change "Other than a real circuit," to "Unlike a real circuit,"

Is another option to slightly alter some of the components (for example to make 1 capacitor 1% lower, or to increase a resistor slightly?