32.768 KHz oscillator using a watch crystal

You can use to produce a 32.768 KHz square wave from a common watch crystal. The output can be fed to a 15 stage binary counter to obtain a 1 second square wave. The circuit on the left using the 4069 inverter is recommended over the transistor circuit and produces a better waveform. The single transistor circuit produces more of a ramping waveform but the output swings the full supply voltage range so it will easily drive the input to a CMOS binary counter.

Source : http://ourworld.compuserve.com/homepages/Bill_Bowden/page11.htm#oscilate.gif

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