oscillator wont simulate correctly

Circuit will not oscillate when I run a time-domain simulation. Tried simulating before and after BJT. Please let me know what I am doing wrong. https://www.circuitlab.com/circuit/696rk45e2ttn/final-project-electronics/

by maddiemueller
May 03, 2024

The period is about 500u, so, by Nyquist, your time interval must be, MINIMUM, half of it, but recommended, 10 times less, and that is a minimum.

You must run the simulation to get a few periods, since the first ones are generally different than the "steady" ones.

Next, a perfect symmetry, which is unreal in the real world, may kill any "starting" oscillation. Against that, I add an imperfection, such as, here, R3=40K and reducing it gradually until I lose the starting oscillation.

Also, check the scale. That my sounds a little bit flat even if it oscillates form minus one uA to plus one uA when displayed at the same time than 150mA

(Note that I recommend removing the timed switches, which required, uselessly, extra computation time, so I don't have to wait to see the result, at least, to get the proof of the oscillation.)

by vanderghast
May 12, 2024

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