Are you sure about that 60Hz?

For the past few weeks, I’ve been blogging my assembly of the transistor clock which is now hanging on the wall of my new apartment.  One of the most interesting aspects of that clock is how it keeps time.

Most clocks today use high precision crystal oscillators or dial out to some atomic clock somewhere (like your cellphone), but the transistor clock actually uses the 60Hz AC coming out of your wall socket to keep time.  While this method was once common use, it’s certainly unconventional by today’s standards.  I decided it would be fun to try to investigate exactly how accurate the 60Hz coming out of the wall is.

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Transistor Clock Part 1: Power and Time Base

So, if you have been following me on twitter, you might have noticed this tweet where I raved about a “Transistor Clock” kit that lets you build a wall clock using 194 discrete transistors and hundreds of other components.  I’ve since purchased the kit and decided to blog my assembly of it.


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