[time-nuts] Regulating a pendulum clock

Bob Camp lists at rtty.us
Mon Aug 9 17:02:32 UTC 2010


For that matter, how hard is it to put it in a vacuum with temperature
control? Gets two big issues out of the way pretty fast. We certainly buy
crystal oscillators that are heated and enclosed in pressure tight
containers (not quite the same as vacuum, but close). 


-----Original Message-----
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of Bob Holmstrom
Sent: Monday, August 09, 2010 12:47 PM
To: time-nuts at febo.com
Subject: Re: [time-nuts] Regulating a pendulum clock

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?

Bob Holmström
Horological Science Newsletter
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