LTspice Tian Probe Fully Differential Amp

Hi Folks,

I am new to LTspice and trying to run a loop gain stability check on a fully differential amplifier. Thanks to this forum (especially Dave Zan), I managed to download an example amplifier with Dave Zan's balun.

When I implement the balun probe, and try to run the Tian method for Loop stability, results seem garbage.

Am I doing something silly? Why is the loop gain looks garbage? It is a simple circuit,

thanks!
 

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Hi Folks,

Thanks to threads by Dave Zan and Sandrohv, I got the differential probe up and running!

I am new to this forum (edaboard.com was my old home). And I am impressed by so many discussions and mostly cordial conversations.

I basically created a subcircuit for a balun. Then using Sandrohv's beautiful LGS probe, connected it up correctly.

You may never see this, but thanks Dave Zan and Sandrohv! Much appreciated,

thanks!