What is Quartz Crystal Chronometer?

• Setting of hours & minutes:  Necessary only when initially setting up the chronometer or restarting it after a long stoppage (highly unlikely).
• Resetting of Seconds hand:  The knob should be pulled out and rotated as required ensuring that positions of the minutes and the seconds hand are perfectly synchronised i.e. When the seconds hand reaches 60, the minutes hand is positioned at a full minute.
• Frequency adjustment: Frequency of oscillation can undergo variation due to normal aging of the quartz crystal, which can result in an appreciable daily rate. This can be adjusted by turning a frequency control’ screw at the back with an insulated screw driver. One full rotation of this screw should cause a change of approximately 0.1 sec per day.
• Test socket:  It is used to check the rate of chronometer. An Electronic frequency meter can be inserted in the socket to measure the final impulses to the second hand. This adjustment should be done at temperatures close to its Standard temperature.
• Standard temperature control:  Temperature Sensitivity

1. They are expected to work reliably between -10°C to 60°
2. However they generally work best at about 20° C offering accuracy better than 0.02sec per day which may go upto 1.5sec per day in case of temperature variations. .
3. Shipboard chronometers are housed inside insulated compartments where generally temperature is maintained between 15° to 25°
4. In case of cold weather, an electric bulb inside the cabinet is kept on to maintain temperature.

How to start the Chronometer against a Time Signal?

1. Disassemble the chronometer.
2. Press the “Stop” button.
3. Set the time of the next radio time signal by pulling and gently turning knob provided for this purpose.      
4. Await the time signal and, release the stop button.
5. Reassemble the chronometer
6. Check the error as soon as possible.

Maintenance of Quartz Chronometer

For disassembling, starting the chronometer against time signals, or battery replacement the procedure laid down by the manufactures should be strictly followed, however, following are general guidelines for these functions: