I have a schematics of a bjt gyrator And I start matrix analysis with help of a Mathematica 7, but I but stuck. I wont to find Zin and then find equivalent inductance. But the expression of Zin is is awfully complicated and its very faraway from L≈C1*R1*R2. So I have a question. Maybe somebody has idea how to analysis this kind of circuits. Or maybe any kind of document that describes this or similar circuit.