[time-nuts] Re: Crazy Clock

[Thomas D. Erb]

School systems clocks have lots of different correction protocols - I call them "predictive motion"  one of the standards sends a short pulse once an hour and a longer one twice a day - sometimes this signal was sent with large frequency generators tied to the  local power grid and notch filters added to clock.  One old story was I believe Stromberg installed a system at a NYC airport in the 50's and everything worked fine during the day until they buffed the floors at night.

There are 24VDC Reverse Polarity movements available out of Europe - that can be easily run with a H-Bridge.

Telechron - a firm which my company grew out of (due to a patent on a self starting clock motor)  - developed master clocks to keep line frequency accurate (based on Tesla's ideas) - they also made large clock systems with a switch that allowed a 120HZ generator to manually advance the clocks - I believe some of these systems are still working almost 100 years after installation.





Thomas D. Erb
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