[time-nuts] GPS disciplined mechanical clocks

Eric Williams wd6cmu at earthlink.net
Thu Mar 5 04:11:43 UTC 2009

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 <sar10538 at gmail.com> 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 -- time-nuts at febo.com
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.

More information about the time-nuts mailing list