Will all this effort to create a good sine wave for use as Component Tester, and all the testing on it, I might as well put the CT to the test which started it all, i.e. the one built into my Hameg HMO2024 oscilloscope.
Nothing easier than that – just hook up a probe to the signal it generates on the front panel, and do an FFT on it:
(yeah, a green trace for a change – the other channels were tied up for another experiment…)
Ok, but not stellar: 1.6% harmonic distortion on the 3rd harmonic – more than with the Phase Shift Oscillator.
The frequency is also about 10% high, although that’s usually not so important for a Component Tester.
PS. The ∆L units should be “dB”, not “dBm” – Hameg says they’ll fix this oversight in the next firmware update.