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I am trying to simulate the circuit below. Why do both low-pass filters show the same behaviour, even though their component values are different?

Circuit

Output

Input

Edit: How stupid of me. I used the label "In" for the both circuit. That is the why I got same result.

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    \$\begingroup\$ When I am simulating them seperatly (on each circuit file) they are filtering as expected. - that's good so, what do you mean when you say this: Why is that so? And how can I avoid it? - what is it you're trying to avoid and what specifically do you need explaining? Also, what do you mean when you say this Both low pass filters have the same behaviour - clearly they shouldn't else why is one set to be 10 kHz and the other is 100 Hz? \$\endgroup\$
    – Andy aka
    Dec 3 '21 at 16:00
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    \$\begingroup\$ having something work the first time around has shattered their world view \$\endgroup\$
    – Stiddily
    Dec 3 '21 at 16:05
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    \$\begingroup\$ These are 100 Hz and 10 kHz LPFs. So why simulate up to 10 GHz??? I would say that up to 10 MHz is more than enough, then you should already see -60 dB on the 10 kHz filter. That would make it more easy to determine the -3dB point. \$\endgroup\$ Dec 3 '21 at 16:20
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    \$\begingroup\$ Do yourself a favour and edit the colours of the labels to be red, not the simulation cards. The labels are far, far more important. \$\endgroup\$ Dec 3 '21 at 17:47
  • \$\begingroup\$ You are definitly right. That's a good idea. @aconcernedcitizen \$\endgroup\$
    – elektronik
    Dec 4 '21 at 22:00
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I think that you'll find that this is "a" definite problem: -

enter image description here

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