In the following diff amp, only one output is taken from collector two.(adsbygoogle = window.adsbygoogle || []).push({});

When I calculate the differential mode gain using the second differential input (-Vid/2) I get a positive gain. When I calculate the differential mode gain using the first differential input (Vid/2) I get a negative gain.

A spice simulation of this circuit shows that the output is positive.

I would then expect to get a negative gain for (-vid/2) and a positve gain for (vid/2)

Does someone know why that is not the case?

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# Differential mode gain

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