live sound collage broadcasts

2.26.19
Whose Time Is It Anyway?


Spectrum images and sounds of time signal stations

Time used to be a casual endeavor.  Before the advent of electricity there was little need to codify the notion of time beyond the capabilities of astronomical measurement.  Sun comes up, sun goes down- time standards were based on the length of the earth’s rotation.    

The solar measurement of a day can vary by tens of seconds over the agreed upon length of 24 hours, leading to a difference in ‘actual’ versus observed time of up to 16 minutes a year.

Enter Greenwich Mean Time.  Greenwich, England was decided as the location of the Prime Meridian at the International Meridian Conference of 1884.  All calculations for Universal Time would be made from this one location, solving the issue of local observational relativity causing variance in astronomical time calculations but still not addressing how the issues of fluctuations in the Earth’s rotational angle affected the goal of establishing a worldwide time standard.

The invention of atomic clocks provided a terrestrially observable time standard that would not vary based on an observer’s location.  The functioning of atomic clocks is too complicated to get into here, but the sketch is an atom exposed to a particular wavelength of energy will release electrons at a particular frequency, which can then be observed.  Think of it as a pendulum constructed with light and energy instead of weights and springs.  The same amount of energy is detectable each time an electron transition occurs, no matter where it occurs on this planet or in what way it is measured.

Most countries run an atomic time service. A dedicated long wave radio transmitter connected to an atomic clock sends out a pulse-modulated time code signal which is used to synchronize clocks for military operations, computer networks, communications services, emergency response, and other essential services.

Each country has its own specific transmission standard for time code.

This next edition of Special Collections will present the clicks, beeps and bloops from time signal radio stations around the world.

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Broadcast date: February 26th 2019
KCHUNG Los Angeles 1630AM



SPECIAL COLLECTIONS is a broadcast project by Sam Rowell.
Each edition is mixed live on the air.