Calculated resonance frequency from L = 70mH and C = 10nF: fres = 6kHz.
Upper trace is the sawtooth with some damped oscillations on the steep rise part.
Lower trace is a magnified part of delayed sweep - delay 2,5ms to see better glitches on the rise part of sawtooth.
Oscilloscope screen-time base:
upper trace: 0.5ms/div,
lower trace: 50µs/div (2.5ms delayed sweep).
Reading from screen - accuracy about 20%, enough for our experiment.
Both - calculated(6 kHz) and measured(5 kHz) frequency are nearly (+- accuracy) same.Worked with: