Retrotechtacular: The Best Pendulum Clock

See the original posting on Hackaday

Would you believe a pendulum clock that can keep time accurately to within one second per year? If you answered “yes”, you’ve either never tried to regulate a pendulum clock yourself, or you already know about the Shortt Clock. Getting an electromechanical device to behave so well, ticking accurately to within 0.03 parts per million, is no mean feat, and the Shortt clock was the first timekeeping device that actually behaves more regularly than the Earth itself.

[Matt Little] passed us this link to an interesting technical writeup (PDF) of the clock. The trick behind the most accurate pendulum clock …read more