[time-nuts] Sidereal timekeeping

Chuck Harris cfharris at erols.com
Thu May 19 11:35:15 UTC 2011


An actual quartz analog wristwatch wouldn't do something so mundane as
to use a 50uf capacitor to drive the coils.  They do this:

DRIVER-A---------------------COIL-----+
......................................|
DRIVER-B------------------------------+


And feed the drivers with these waveforms:

1.5V..........+-+.............+-+.............+-+......
..............|.|.............|.|.............|.|......
A-------------+ +-------------+ +-------------+ +---...

1.5V..+-+.............+-+.............+-+..............
......|.|.............|.|.............|.|..............
B-----+ +-------------+ +-------------+ +-----------...

Where the pulses alternately come from A and B every second.

If you use a PIC to drive the clock, the driver is easy to program in software.

-Chuck Harris

iovane at inwind.it wrote:
> I understand now why most analog wristwatches do tick every two seconds when
> the battery is low. I believed the logic used this trick to signal low battery.
>
> Antonio I8IOV




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