Naturally, it's not perfect. You're right in that the S inverters don't seem to work over as wide a frequency range without changing the capacitor and resistor values. I seldom use an S part for this sort of oscillator.

I'm aware that manufacturers recommend the use of unbuffered CMOS for oscillators. However, in this particular circuit, it seems to accept most technologies over a wide range of frequency. I substituted standard TTL, L, LS, F, ALS, C, HC, HCT, AC, ACT, AHCT, and HCTLS components with no observable difference, aside from the fact that the C and L parts didn't do so well at frequencies above 6 MHz. The problems I have noticed over the years with S inverters is startup. With the proper cap and resistors, however, they seem to start just fine.

I have had limited success with this at frequencies above 25 MHz. It's never refused to work for me in any MCU or microprocessor application, however.

RE