General Asylum

Way overpriced for its fundamental task and average accuracy

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A 'thermocompensated movement' is just a fancy way of describing a temperature compensated quartz crystal oscillator used as the time base or frequency reference for the clock. These small TCXO modules are pretty cheap. The temperature compensation helps keep them on frequency over a wider range of ambient temperature.

However, better accuracy is achieved in typical $25 radio controlled wall clocks that are synchronized to an atomic clock. [United States Time Standard atomic clocks, NIST-F1 and NIST-F2]

A time code signal (IRIG-H) derived from the atomic clock is transmitted over the air and received by the radio controlled clock periodically. Many of these clocks sync late at night or in the wee hours of the morning when radio propagation is best. In the USA, these clocks have receivers that operate at 60KHz. The WWVB transmitter is operated by NIST and located in Ft. Collins Colorado. Other similar systems are available worldwide and operated by other countries.

We have a few $25 - $45 radio controlled clocks throughout our home and my $300 wrist watch uses the same technology. They are never more than 1 second off or 1 second apart from each other throughout the entire year as they are synchronized nightly.

Can't say the same for the McIntosh clock. It relies solely on it's own internal TCXO which is probably good for no better than about 10 - 15 seconds per year.... AND it costs $1800 !!



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