I thought that A = 1 + Rf/Ri for an op-amp non-inverting amplifier? With a 1mV input, I'm getting output voltages in the uVs...
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1\$\begingroup\$ The LM741 was obsolete decades ago, please get a better op amp. \$\endgroup\$– HearthCommented Sep 22, 2023 at 18:57
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The feedback is incorrect.
As there is 4.5V on positive input, by rules of how op-amps work, there must be 4.5V on negative input too. Which means, there must be about 45V on output, which isn't possible with 9V supply, and the op-amp can't handle supplies beyond +15V anyway.
I bet what you wanted is to have a single-supply circuit with AC coupled feedback to ground, so that only AC component is amplified while DC has gain of 1.
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\$\begingroup\$ Thank you! The first part makes a lot of sense. Is this a problem on the buffer too? Also, can you elaborate on the single supply circuit? I think I understand it in principle, but I’m not totally sure about the ac coupled feedback part. \$\endgroup\$– Eli YCommented Sep 20, 2023 at 18:12
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\$\begingroup\$ Never mind! Got it! Thank you again for helping me out! \$\endgroup\$– Eli YCommented Sep 20, 2023 at 18:23