xtal_freq .vs. correction about si5351arduino HOT 3 CLOSED

1/2x at 5 MHz not 1.2x ...

from si5351arduino.

The correction factor is applied to any frequency entered, but any remaining error will be scaled based on the relationship between the output frequency and the reference oscillator frequency. That's just the nature of how a PLL works.

Yes, at VHF the error is approximately 15x what it is at 10 MHz. So 1 Hz uncertainty would translate into a potential of +/- 15 Hz at 150 MHz.

A higher resolution could be put into the correction factor to give a more accurate calibration, but you'll never totally get away from the effect that the error scales in proportion to the output frequency. However, I would think that 0.01 Hz resolution in the correction factor would be sufficient for almost all needs.

I'd love to hear if there are others looking for a higher resolution calibration.

from si5351arduino.

OK, correction factor is now specified in parts-per-billion, so that should give extra precision for those of you with very good frequency counters.

from si5351arduino.