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I'm trying to build a basic square wave oscillator using an astable vibrator made with an op-amp for my Intro to Circuits class.

Unfortunately, I cannot get LTspice to simulate the oscillations.

I've tried a good chunk of the op-amps available. I've also tried varying resistor values, VCC and VEE, capacitance, transient settings, and the initial voltage on the capacitor. I can get this to somewhat simulate on Farstad, but how do I get it to simulate on LTspice?

Edit- I am aware that voltages attached to VCC and VEE have incorrect polarity, it still doesn't work if they are correct.

Edit2- The capacitance in 100 nF, voltage is read from the output of op-amp. Zooming in on the photo should help if you have difficulty reading some of the values.

Edit3- This is the latest version of LTspice running on a Windows 11 machine.

enter image description here

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    \$\begingroup\$ There are problems with Astables on the bench and on the sim .Old people have seen this but they cannot read your photo so cant answer your question. \$\endgroup\$
    – Autistic
    Nov 15, 2023 at 4:23
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    \$\begingroup\$ The images don’t show up well, small and bad color scheme. \$\endgroup\$
    – GodJihyo
    Nov 15, 2023 at 4:32
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    \$\begingroup\$ Also Win 7 isn't supported anymore. \$\endgroup\$
    – MiNiMe
    Nov 15, 2023 at 5:03

1 Answer 1

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Here is one problem: The output of the op-amp is connected to GND.

There may be other problems.

enter image description here

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    \$\begingroup\$ Taking the output off ground and changing my positive input resistors to lower values seemed to have fixed it, thank you. \$\endgroup\$
    – Jgely
    Nov 15, 2023 at 6:44

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