EG8010 frequency Accuracy

Author	Message
phil99 Guru Joined: 11/02/2018 Location: Australia Posts: 2626	Posted: 10:04pm 24 Jan 2025       I think @oreo's issue is with a synchronous motor clock or mains referenced digital clock accumulating the frequency error. The short term accuracy of the grid is usually within 0.03 Hz but over the course of a day it is corrected to average exactly 50Hz (60Hz for Canada). So clocks never need adjusting. Without external correction a crystal oscillator will always drift. It is possible to pull the frequency of a crystal down a little by adding a few pF in parallel. Experiment with values in the range 1pF to 5.6pF. Larger values than that may cause instability. Use an NPO type for temperature stability. It still won't be as good as the mains though. For that replace the crystal with a GPS disciplined precision oscillator.