Hello all, I'm having trouble observing basic behavior of an open-loop op amp test circuit. I should expect that as I move the voltage input (the blue channel) towards 0 V, the output voltage (the yellow channel) should dither. But I'm not seeing the output voltage budge at all, while I'm sweeping my oscilloscope. I'm using an LM311P op amp and powering it with +/- 15 V from 2 DC power supplies stacked to be symmetrical. I tried swapping out with a new LM311P, but that didn't make a difference.
The black clip is GND, the yellow clip is -15 V, the red clip is + 15 V
Could it be that I'm using the wrong type of op amp?