In rec.radio.amateur.homebrew Jeff wrote:


I don't know what you guys are seeing. The two pendulums of the Shortt
clock are in lock step. The fact that they are only compared every 30
seconds does not change the nature of the design.


What we are seeing is that even after the 30 second 'kick' the 2
pendulums are NOT in phase.

They may well be 'a bit closer' in phase, but the kick just moves the
difference a fixed small amount in one direction, which may be
sufficient to bring the phases closer, or it may be too much and go
through the in phase point. With the design there is no time where the 2
pendulums are *held* in phase.

The design in fact relies on the fact that the phase of the 2 pendulums
is constantly changing.

Jeff


https://en.wikipedia.org/wiki/Shortt...sync hronizer

"This feedback loop functioned as an electromechanical version of a
phase-locked loop..."


--
Jim Pennino