Piezo sounder admittance experiment

Use Python 3.9 or newer. No third-party packages are needed.

  python3 piezo_admittance.py synthetic-sweep.csv
  python3 test_actual_program.py -v
  python3 piezo_admittance.py my-sweep.csv --series-ohm 998

The first command reads constructed input for a 10 nF control and an
illustrative piezo model. These values are neither a PS1720P02 fit nor
physical readings. The second command exercises the delivered CLI.

For your data, copy observations-blank.csv to a new file and complete
both runs. The oscilloscope channels measure VIN and VD together.
Both reference clips and the generator shell remain on common 0 V.
Use the oscilloscope-measured Vpp and rising midpoint crossings.
Enter VD crossing time minus VIN crossing time in microseconds.
Use the same recorded frequencies for both fixture names. Remove an
unusable point from both runs and retain it separately in your notes.
Add --series-ohm with the measured resistor value within 900–1100 ohms.
Nominal VD probe correction is 10 MΩ and 15 pF. Separate loaded outputs
preserve the model input admittance before subtraction.

The full bench procedure is in the article. Disable generator output
before rewiring and verify the sine stays under the 2 Vpp setup limit.
Take probe mismatch and measurement repeatability notes separately.
This is a host-only analysis of electrical signals. No firmware,
physical measurement, acoustic calibration or verified resonance is included.
