Chronometry: Glashutte quartz chronometer

[Snapper]

Not sure whether to post this here, New Aquisitions or Electrical Horology so moderators please move if you see fit.

I have just acquired this Glashutte to kind of complete my chronometer collection. I now have them dating from 1832. The great thing is that this came with it's padded guard box, operator's manual, factory and a later Sewill's rating certificate, and details of the ship in which it saw service. It runs perfectly and is in superb condition. Any factory history would be welcome or indeed any further details about construction etc.

 

[Tom McIntyre]

Thanks for posting your chronometer. Mine is essentially identical except only the chronometer itself and ser. no. 2216. When I went to check on it I noticed the batteries had run down. I believe they are scheduled for replacement every two years but my 2007 set lasted at least 8 years. I also noticed it ticks along happily on only two batteries of the four.

 

[Snapper]

Thanks for your response. The operator's handbook advises the batteries are changed every year, but clearly the advice is aimed at maintaining reliability at sea.

Only two batteries are used at one time. The secon slot enables batteries to be changed without stopping the chronometer. Insert two new batteries in the empty slot then remove the old ones.

There seems to be a dearth of technical information about these machines. The manual stresses they need no routine maintenance other than changing batteries, but I assume pivots will have a finite life.

 

[Tom McIntyre]

I will take the two extra batteries out! I don't know that I have heard of any other battery operated timepiece with "maintaining power."

With a single stepper driving the motion works, I would imagine a very long lifetime. The circuit components will also eventually fail from chemical deterioration. That may happen sooner than the pivot wear.

 

[Luis Casillas]

Google came up with this page in German:

• http://www.glashuetteuhren.de/kalib...nbetriebe/kaliber-71-quarz-marinechronometer/

My German is very, very rusty, but I can make some of it. Chrome's translation feature figures out nearly all of it anyway. Some of the specs:

• Crystal frequency 32.768Hz
• Operating voltage 3V
• Power reserve 365 days
• Stability at constant + 20 ° C ± 0.01 s / d
• Greatest deviation at + 4 ° C to + 36 ° C ± 1 s / d

32,768 is the most common quartz clock/watch frequency. Looking at watch crystal spec sheets and doing some back-of-the-envelope calculations, it sounds like the chronometer (unsurprisingly) has better temperature compensation than a typical quartz timepiece, but not by a huge amount.

 

[Snapper]

I will take the two extra batteries out! I don't know that I have heard of any other battery operated timepiece with "maintaining power."

With a single stepper driving the motion works, I would imagine a very long lifetime. The circuit components will also eventually fail from chemical deterioration. That may happen sooner than the pivot wear.

Again the "maintaining power" is for use at sea as it it would be highly undesirable for the chronometer to be stopped even for a few seconds. I believe the Wempe chronometers keep running for up to five minutes by means of capacitor discharge without batteries to enable fresh cells to be inserted.

 

[Snapper]

Google came up with this page in German:

• http://www.glashuetteuhren.de/kalib...nbetriebe/kaliber-71-quarz-marinechronometer/

My German is very, very rusty, but I can make some of it. Chrome's translation feature figures out nearly all of it anyway. Some of the specs:

• Crystal frequency 32.768Hz
• Operating voltage 3V
• Power reserve 365 days
• Stability at constant + 20 ° C ± 0.01 s / d
• Greatest deviation at + 4 ° C to + 36 ° C ± 1 s / d

32,768 is the most common quartz clock/watch frequency. Looking at watch crystal spec sheets and doing some back-of-the-envelope calculations, it sounds like the chronometer (unsurprisingly) has better temperature compensation than a typical quartz timepiece, but not by a huge amount.

Thank you fot that information. I have a German speaking friend who I will ask to translate.