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1/100 minute analog timer - what for?
metrologist:
I have this timer but instead graduated to 100, and without a minute hand (it has the center minute circular piece but no arm) and the reset does not reset the minute, which seems intentionally built that way.
What would such a timer be used for? I understand decimal timers but one that only counts to 1 minute?
https://www.ebay.com/itm/155035806178
TimFox:
According to the eBay listing, it's a darkroom timer.
Are you sure you understand the calibration correctly?
metrologist:
Yes, but what I read is that developing time is generally minutes and exposure is in seconds, and all "darkroom" timers I've seen are graduated in seconds with a minute hand. I'm pretty sure the hand did not just break off as the circumference is fully painted and smooth, and also that there is no internal lever to reset the minute wheel...
With 100 units to the minute, it's not too easy to figure out where 17 seconds is, for example.
Calibration? Yes, I popped the hood and there is what I think is called a regulator thingamajig. I have one of those regulator apps on my phone too, I think called a timegrapher.
Operation is simple. The left lever has run and stop positions. The right lever is spring loaded and resets the 0.6 second hand only.
I was half tempted to glue on a minute hand until I realized the minute wheel is not reset. I'd have to figure out that part of the mechanism.
thm_w:
https://www.ebay.com/itm/166255177630
https://afterglowretro.com/2013/08/21/junghans-darkroom-laboratory-sports-timer-made-in-germany-circa-1950s/
https://www.hanhart-stoppuhren.com/en/products/precision-mechanics/split-seconds-addition-timer/23/split-seconds-addition-timer-1/100-min.-industry-model
Maybe a 60s timer with 1/100ths of a second and the 1/100ths hand is broken?
metrologist:
One revolution is one minute. Maybe a decimal minute is more common in other countries. I'm an American ogre.
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