Nah! No ropes or gears. Just a SS tank on steel stilts and a big mercury reservoir and a pump.
And it might not have to hold tons. Think of a hollow SS donut with the pendulum in the clear space. KISS, -John =============== > Ahhh, this is more like it! Large gears and thick ropes moving > heavy weights up and down. :) > > Of course, you wouldn't want anything digital doing this. Just > a large pendulum clock driving a maze of gears that calculate > solar and lunar positions. > > Bill Hawkins > > -----Original Message----- > From: J. L. Trantham, M. D. > Sent: Monday, August 09, 2010 3:10 PM > > Personally, I would get out of the way. : ) > > Joe > > -----Original Message----- > From: Ian Sheffield > Sent: Monday, August 09, 2010 1:17 PM > > What happens when the rope breaks? > > -----Original Message----- > From: J. Forster > Sent: 09 August 2010 19:10 > > You could put a large mass of concrete or somehing above the clock and > crank it up and down, to balance out the computed gravity changes. > > :) > > -John > >> Unfortunately Gravity is not constant. Pendulum clocks show cyclic >> errors >> due to the influences of the Moon's and Sun's Gravitational fields. I >> forget the amounts but it is in the region of parts in 10 to the 7, >> which >> is easily measurable. >> >> This limits the compensations one can put into a pendulum clock. >> >> >> -----Original Message----- >> From: mike cook >> Sent: 09 August 2010 18:21 >> >> On 09/08/2010 18:46, Bob Holmstrom has written: >>> >>> Food for thought. >>> >>> I find it interesting that no one has suggested alternatives to >>> improving the performance of a pendulum clock other than controlling >>> it with a higher performance clock. If the goal is a better clock why >>> not attempt to understand the source of the errors and work on methods >>> to control or compensate for them? Teddy Hall has been taken to task >>> for using a quartz controlled oscillator to measure the amplitude of a >>> pendulum in the control loop of his Littlemore clock. >>> >>> Tom Van Baak has developed techniques for analyzing the performance >>> and hence potential error sources of pendulum clocks - perhaps he will >>> share some of his work here. >>> >>> Horological history is full of many attempts at solutions to the >>> problem, but it would seem that the creativity of this group might >>> generate some new ideas that are more in the spirit of better >>> timekeeping than attaching the pendulum to a better oscillator. >>> >>> How about a wireless controlled device attached to the pendulum that >>> changes its position based on error sensor readings, not time errors, >>> but instead, temperature, barometric pressure, gravity, etc. that >>> would maintain a more constant pendulum period? >> >> Yup. We have temperature and pressure ICs available , I think that >> gravity is pretty constant if the clock isn't being moved about. >> Humididty might also need logging aswell. So it should be easy enough to >> predict the pendulums response to changes given a reasonable time of >> observation. >> That said, clocks have always been adjusted against better >> references.. IIRC Harrison (and probably others) was using star transits >> to regulate his long case clocks. >>> >>> Bob Holmström >>> Editor >>> Horological Science Newsletter >>> www.hsn161.com > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
