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wooden box, gimbals, chronometer case, and a clockwork which incorporates a fusee 

mechanism for near-constant winding force as the mainspring winds down, a detent 

escapement, and a temperature-compensated balance wheel fitted with a helical 

hairspring. 

When the US Navy realized the upcoming need for thousands of such chronometers in 

the years prior to World War II, the only company which could fill the need was 

Hamilton Watch Company of Lancaster, Pennsylvania.  Hamilton could meet the need if 

the basic design of a Ulysse-Nardin chronometer was exactly copied, except for the 

balance wheel assembly.  Hamilton had developed a better way to create a 

temperature-compensated balance wheel that would not require the time-consuming 

and laborious process of regulation that was required by the Swiss-pattern 

chronometers. 

Figure 9:  Ulysse-Nardin Marine Chronometer, Predecessor to Hamilton 21

 

                             

 

By making the balance wheel an unbroken ring of stainless steel supported by a simple 

two-spoke arrangement made from Invar (a metal alloy with near-zero change in 

dimension with temperature change), a Hamilton could manufacture a balance with 

built-in temperature compensation not requiring many days of regulating.  Hamilton 

produced about 10,000 such chronometers prior to and during the war, and these were 

found to be the most reliable and precise chronometers manufactured until that time. 

The advantages of a mechanical, manual-wind chronometer are its reliability and 

trustworthiness.  As long as the chronometer is wound each day, accurate time is 

Summary of Contents for The Time Traveler's Clock

Page 1: ...THE TIME TRAVELER S CLOCK The Project s History and User Manual Euclid Laboratories Inc Teaticket MA...

Page 2: ...igin of the TTC o How Did This Project Begin o Why Do You Need a Time Traveler s Clock o What if Time Travel is Impossible History of Prototypes o Cesium Breadboard Prototype o Pyramid Cesium CSACGPSD...

Page 3: ...ation o Reading Times from the Display Panel o Reading Time and Winding Reserve from the Chronometer Time keeping Verification Servo Controls o ServoSync o Rate Atomic and Rate Error Measurement o Rat...

Page 4: ...Locking the Chronometer for Storage or Shipment Appendices Schematic Diagram Description of the Circuit Operation Firmware...

Page 5: ...ated which utilizes a silicon real time clock RTC chip to provide time in case the GPS signal is unavailable and the CSAC atomic clock fails or runs out of power The RTC chip contains a temperature co...

Page 6: ...lculated from the Hamilton chronometer even if the GPS and atomic references are not functioning for example if electrical power has been lost for longer than the backup batteries will maintain operat...

Page 7: ...ll its displays and on the Hamilton chronometer Origin of the TTC How Did This Project Begin After discovering and rebuilding the Time Viewer originally constructed by Leonardo da Vinci the present in...

Page 8: ...system isn t operational You might travel to the future when the time standards and navigational systems are completely different from what we have now but you ll be able to find some form of electric...

Page 9: ...lays for time from the GPS and the RTC A circuit was incorporated to allow re setting the RTC from the GPS whenever desired Additional problems to be worked out were an automatic winding system a back...

Page 10: ...wards which would damage the chronometer a One way Clutch is pressed into the Winding Gear and rides on the hardened surface of the Winding Spindle When each winding cycle is completed the Winding Rac...

Page 11: ...er needed to operate the rating circuit and printer was changed to a simple contact closure mechanism which is available in a few of the Hamilton 21 chronometers which were made in the last century Wh...

Page 12: ...al cubical mahogany box like what has been traditionally used for marine chronometers but increased in size having more internal volume and a smaller footprint than the pyramid The cube box had a lowe...

Page 13: ...n a separate enclosure and connected by a cable to the rear panel of the box In addition to the GPS Antenna connection on the rear panel SMA connectors supplied the MAC 10MHz reference frequency the M...

Page 14: ...n reference frequency The rubidium MAC was replaced with the cesium CSAC used in the Cesium Breadboard Prototype Otherwise the MCB Prototype was like the Cube Box Prototype and used the same electroni...

Page 15: ...ted balance wheel that would not require the time consuming and laborious process of regulation that was required by the Swiss pattern chronometers Figure 9 Ulysse Nardin Marine Chronometer Predecesso...

Page 16: ...he TTC keeps the mechanical chronometer synchronized to GNSS or atomic precision by means of a servo mechanical system It has been found that a very small rotation of the chronometer every second will...

Page 17: ...over even if satellite signals are lost By itself the uBlox M8F receiver has a holdover precision of 1 x 10 7 or 8 milliseconds per day If an atomic reference signal is supplied then the holdover prec...

Page 18: ...esses TTCs use atomic frequency standards based upon the oscillations of cesium or rubidium atoms These are the most precise reference standards available that can be used in portable equipment The Mi...

Page 19: ...Figure 12 Cesium Chip Scale Atomic Clock Circuit Board...

Page 20: ...he gimbals of the chronometer by means of a lever and a linkage Two problems remained how to mount the chronometer and its gimbals in such a way that the chronometer can be rotated by this small amoun...

Page 21: ...bearing balls The inner and outer rings and the plastic ball carrier are cut to provide clearance for the chronometer to be tilted forward for manual winding Again a servo motor and linkage provides t...

Page 22: ...es to match the outer periphery of the ring The stainless steel ring is attached to the chronometer gimbals The motion is transmitted from a servo motor via a linkage as in previous designs The ring i...

Page 23: ...Figure 16 Time Traveler s Clock System Schematic Diagram...

Page 24: ...Figure 17 Hamilton 21 Chronometer Starting Instructions...

Page 25: ...TTC Installation and Operation Manual...

Page 26: ...s o Main Power Battery Charger and Connecting Cable 1 The main power supply consists of a battery backed uninterruptible power supply UPS that supplies 12V DC current to the Main 12V power connector o...

Page 27: ...ar panel by turning it so the red dots align and pushing it on No tightening is required The printer cable may be removed by grasping its knurled sleeve and pulling straight out 2 Using the Printer is...

Page 28: ...onds This display is completely independent from the other timekeeping systems and serves as a backup and confirmation of proper operation The time displayed on the Real Time Clock display may be seve...

Page 29: ...new from the factory although the chronometer should still be operating and will not need to be reset o If power is lost for over 24 hours the chronometer should be manually wound to keep it running...

Page 30: ...f the chronometer will go into stand alone operation without ServoSync and its rate will be measured against the GPS Atomic reference the result will be printed on the Printer exactly as it would be a...

Page 31: ...l Place the winding key onto the small square winding stem on the winding mechanism If the AutoWind mechanism has been removed the key goes directly into the hole surrounding the chronometer s winding...

Page 32: ...igation using chronometer time and sextant according to normal navigational procedures Metal Cube Case Operation and Alternate Configurations o The Cube Case may be opened by pressing the upper latch...

Page 33: ...nd insert the new spool with the paper tape running out the bottom of the spool o Close the front cover of the printer o Operation of the paper feed can be verified by pressing the small feed button o...

Page 34: ...Figure 21 Gimbal Locking...

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