GPS 1PPS Tick

If you use the 1 PPS (Pulse Per Second) output of your GPS receiver to help set the clocks in your shop, this tiny circuit will make
the job a little easier.

The CD4093 sits quietly during most of the second and comes alive during the 1 PPS (positive-going) pulse from the GPS receiver.

While the pulse is high, the oscillator runs at an audio rate. For a 20 mSec wide trigger, the tone becomes more of a 'tick" like the WWV
transmission of 5 cycles of 1 KHz each second.