On Fri, May 16, 2025 at 09:18 AM, alan victor wrote:
You (I) can turn intepolation off.
That would be fine.
I think some of the L & C vendors that offer Touchstone files generate them from simulations, not from raw VNA data. I don't think they're trying to hide any issues with their parts. They may just want to clean up the data. Whenever S11 and S22 are identical, I suspect a simulation. I can also check with the Y21 series-through measurement method. It suppresses stray shunt capacitance. If Y21 and the usual S21 series-through method yield identical results, I think the data is simulated. I believe all component test fixtures, no matter how carefully designed and built, have some residual shunt capacitance.
Brian
