I don't get what is wrong with my sheme and why it doesn't wotk, I would be really thankfull if someone points out what am I supposed to fix

I am supposed to make a low-pass filter and perform AC analysis
here is what I get when I start the analysis
No compatibility mode selected!
Circuit: KiCad schematic
Background thread stopped with timeout = 0
Reducing trtol to 1 for xspice ‘A’ devices
Doing analysis at TEMP = 27,000000 and TNOM = 27,000000
Initial Transient Solution

Your input voltage source V_in1 is floating on the left (just connected to a label?). Pin 2 should be grounded, the label has to be placed at pin 1 of the voltage source.

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Thank you, I got it and fixed it, but now getting “Error: vector frequency not found!” When trying to add V out signal :confused:

Unfortunately you have not given enough information for providing a concise answer.
What are your KiCad and ngspice versions ?
What have been the steps you performed to start the simulation?
What is the simulator output?
What have you done to watch the results?

This problem has gone somehow, now I have plot, but it doesn’t seem to be correct because the filter have to be low-pass, and mag with phase have to go down.


Here is edited filter

and here is what I am supposed to recreate
Sallen-Key_LP

You have R2 in the wrong spot in kicad.

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Thanks a lot, It fixed everything!