Fourier analysis on phase shift oscillator skewed by initial buildup to oscillation?

Is there a way to start a transient analysis at time t=0, but not save simulation results until after the "transients" have died out for subsequent fourier analysis?
When doing a fourier analysis of the output of a phase shift oscillator, the THD values from simulation are much higher than those from measurements on the same circuit.  I am assuming this occurs because it takes a finite length of time for the oscillator output to reach the expected output voltage magnitude and frequency.  Including this transient regime in the fourier analysis would skew the results. 

Hello,
You can find more information about the transient analysis at this tutorial; Configuring a Transient Analysis in Multisim and you can also find information on fourier analysis here; Configuring a Fourier Analysis in Multisim.
Hope this helps!
Regards,
Sharanya R
Market Development Engineer
National Instruments

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