Just to put in my twopenny worth; In the current (March) issue of OZ electronics magazine "Silicon Chip" is a project to lock a cheap battery operated clock to a GPS derived signal.. Uses a Jupitor type GPS head unit to receive the Sat"s signals. Cheers Arie Schellaars VK3DBF
--- On Thu, 5/3/09, Neville Michie <[email protected]> wrote: From: Neville Michie <[email protected]> Subject: Re: [time-nuts] GPS disciplined mechanical clocks To: "Discussion of precise time and frequency measurement" <[email protected]> Received: Thursday, 5 March, 2009, 8:35 AM Hi Jim, a "seconds Pendulum" has frequency of 0.5Hz, and so your subwoofer would need 0.5 hz response if it is going to shake walls. Being a purist I must point out that at 0.5 Hz the sound energy would be in the form of pressure which is very weakly coupled to a pendulum. The only coupling would be buoyancy, and that would need a 1Hz signal to give two reductions in apparent gravity per cycle. Allied to this discussion is the Loomis effect, discovered by the American millionaire who had three Shortt clocks running in his basement. They synchronised unless aligned at 120 degrees to each other. I wonder weather they were shaking the bedrock, or maybe the gravitational attraction between the 10 kg pendulums may have synchronised them. (See "Tuxedo Park" by Jennet Conant) He qualified as the first time nut. cheers, Neville Michie On 05/03/2009, at 5:22 PM, Jim Palfreyman wrote: > So if I set my GPS locked 3325B to 1Hz (sine wave) and put that > into my M&K > subwoofer and sat that next to my pendulum clock (with its ~1m long > Reifler > pendulum) it should keep perfect time. > > Beauty! > > > > 2009/3/5 Tom Van Baak <[email protected]> > >>> 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. >> >> Eric, >> >> Precision pendulum clocks, when mounted near each other, >> have been known to eventually get into phase lock. So one >> idea is to add a GPS 1PPS driven bass speaker or solenoid >> or some sort of thumping contraption. Perhaps eventually the >> pendulum clock would lock to the vibrations on the the wall. >> >> /tvb >> >> >> >> _______________________________________________ >> 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. Stay connected to the people that matter most with a smarter inbox. Take a look http://au.docs.yahoo.com/mail/smarterinbox _______________________________________________ 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.
