Continuous sweep clock mechanism...

Thread Starter


Joined Nov 29, 2005
There is a type of clock mechanism that is silent, no tic-tac, the second hand moves smoothly. Been trying to find a schematic on how it works with no success.
Would you know details or a generic schematic ? I can see uses a crystal in its circuit, and a spinning motor with the usual gears. I want to know if replacing only the crystal can make it run faster.



Joined Jun 4, 2014
Very likely the clock speed will follow the crystal frequency but I have no idea how far you could increase (or reduce) the frequency before it would stop working. There would be both mechanical and electronic reasons for such limits.

Thread Starter


Joined Nov 29, 2005
The mechanism will not be used as clock but as "turntable"
If guessing works, will a 65.536 KHz crystal make a turn in 30 seconds...:rolleyes:


Joined Aug 1, 2013
Just one of the many things that could be a problem when running at 2x its design speed: the speed of the motor driver transistors and shape distortion of the motor drive signals.



Joined Jan 23, 2018
Perhaps the mechanism described is not anything other than a mechanical drive with a synchronous motor. And certainly a synchronous motor with just a bit of inertia driven with a 60 hZ sine wave will be very smooth. So that would be a crystal oscillator with a suitable divider driving a resonant circuit so that something close to a sine wave is produced. The hard part is the mechanical portion.
An alternative is to use mains power and a standard clock gear set. Not very electronic, but delivering the requested performance.