[time-nuts] 1PPS to 32.768 khz

Dave Martindale dave.martindale at gmail.com
Wed Oct 19 09:15:15 EDT 2016

If the "big digital clock" doesn't display the time with fractional-second
precision, then it only needs to be updated at 1 Hz, which can be done with
the 1 PPS directly.  Consider replacing the 32 kHz crystal, divider chain,
and microprocessor with a new microcontroller that takes 1 Hz input and
drives the display in the same way.

For an extra bonus, use a microcontroller with a serial port, and connect
the GPS receiver serial output to the serial port on the micro.  Then you
can decode the serial data stream from the GPS, and automatically set the
clock to the correct time after a power failure - something the original
clock could not do.  As a double bonus, make the clock display leap seconds
correctly when they happen.

- Dave

On Tue, Oct 18, 2016 at 10:03 PM, Lee - N2LEE via time-nuts <
time-nuts at febo.com> wrote:

> 1. Does anyone know of a device that will take a 1PPS GPS timing signal
> and generate a 32.768 kHz sine wave output ?
> I have big digital clock that uses an 8 bit micro processor and an
> external 32.768 crystal. Obviously the external crystal is
> awful for accuracy.

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