A recent thread talked about noisy clocks (1 tick per second). Some of you may have noticed that it's now possible to buy cheap quartz clock movements that have a continuous-sweep second hand, and don't tick once per second. For example, klockit.com sells two different brands (Seiko and Quartex, the latter is owned by the same company that owns klockit).
AFAIK LaCrosse is the only company making consumer-level quartz clocks with this feature, and only on certain models. I've found that the plastic gears do make some noise, especially with a large clock face that acts as a resonator, and they may be audible in a quiet room. But IMHO they're less bothersome than 1 tick per second. A few years ago I put a 'scope on one of the Quartex movements (pic attached, same pic at http://www.panix.com/~rbean/clock/clock-01.jpg ) Like other quartz clocks, they use a "Lavet" type stepper motor https://en.wikipedia.org/wiki/Lavet-type_stepping_motor But the electronic timing and mechanical gearing are different (16 pulses per second). The amplitude is equal to the battery voltage (I think I used a lithium primary cell, which is a slightly higher voltage than alkaline). Some time ago, someone on this list mentioned that he knew someone who worked with the controller chips in cheap clocks and watches. If anyone knows which chip runs these things, I'd love to see a data sheet. They seem to keep remarkably good time for something that costs so little.
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