Can anyone explain why the output is so distorted and weird?
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1\$\begingroup\$ How is the op amp powered? \$\endgroup\$ – Leon Heller Oct 29 '16 at 16:21
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\$\begingroup\$ What were you expecting the output to look like? \$\endgroup\$ – The Photon Oct 29 '16 at 16:23
You have the op-amp connected a comparator, with the (+)input as the feedback node. In other words, you are using positive feedback.
If you want a linear amplifier, then you must use the (-)input as the feedback node. Swap the (+) and (-)inputs in your circuit.
It's pretty much what I'd expect to see for an opamp configured as a comparator with a small amount of positive feedback.
If you we're trying to create a high gain linear amplifier swap the input pins to get negative feedback and a gain of about twenty.