In the evolution of timekeepers the SHORTT CLOCK was one of the great milestones.
see http://www.electric-clocks.nl/clocks/en/page10.htm This clock used a pendulum running free to synchronise another pendulum that did all the housekeeping work. The work pendulum was adjusted to be a little slow and a thin leaf spring was picked up by a relay if the phase was too slow and added a slight gaining rate until the phase was restored. A little like switching a tiny capacitor in and out connected to an TCXO to keep it disciplined. These clock kept very good time. Cheers, Neville Michie On 05/03/2009, at 3:11 PM, Eric Williams wrote: > Bryan Mumford (bmumford.com) did a lot of work developing pendulum > clocks > that were driven by a Fedchenko electromagnetic drive. The drive > circuit > would both put energy into the pendulum and use the pulse to drive an > electric clock face to display the time. He never got to the point of > disciplining the clock, but he did note that you could make fine > adjustments > in the period by varying the drive current which changed the > amplitude of > the pendulum swing and changed the period. (Larger swings ran > slower, as I > recall.) You could theoretically discipline such a clock by > varying the > current to lock the pendulum to a GPS source. It wouldn't really be > mechanical, more of a hybrid, but I don't know how you'd discipline a > mechanical clock with a system that had to drive in parallel with > the escape > mechanism, the two would fight each other. > > On Wed, Mar 4, 2009 at 3:52 AM, Steve Rooke <[email protected]> > wrote: > >> Has anyone looked at locking an old mechanical clock to precise time? >> What I'm thinking of is something like an old cuckoo clock. The rule >> is that the clock remains basically standard and is only steered by >> the external source, say, by a magnetic pulse to the pendulum, IE. no >> physical connection. Obviously the correct period of the pulse would >> have to fit the timing of the pendulum. OK, it seems pointless as you >> can't read time with any real accuracy on something like a cuckoo >> clock but I'm sure there is the likelihood of something like this >> being done by someone like us. >> >> 73, >> Steve >> -- >> Steve Rooke - ZL3TUV & G8KVD & JAKDTTNW >> Omnium finis imminet >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/ > time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
