The Lathem Time Company is best known for their time clocks. They have also made synchronized clock systems for many years. At the end of the 2000s they introduced their AirTime system, a wireless synchronized system that allows customers to install a clock anywhere they want without having to deal with traditional wiring. The system is controlled by a small master clock, which gets the current time from the NIST Atomic Clock and transmits to any compatible clock within a 500 foot radius. Other master clocks can pick up these signals and transmit them as well, expanding coverage. The entire system is battery powered, and Lathem had a solar charged version of wall clock as well.
Other companies do something similar, Primex and Sapling coming to mind. However, Lathem, being an “older school” clock company, built their Airtime clocks to the same standards of the clocks they’ve offered for decades, with offerings of a metal case, large numbers, etc. Unfortunately, Lathem discontinued the line a few years ago. I don’t like the plastic clocks available from other companies. It’s a shame Lathem stopped their Airtime line.
Now, one can buy clocks in both digital and analog flavors that synchronize directly with the NIST Atomic Clock, but the AM band used to transmit this information often fails to get to clocks on the interior walls of large buildings. Hence Lathem’s system where the master clock can be placed in an ideal location and then transmit the data to clocks anywhere in a facility.
The clocks rarely come up on eBay, as the system was never very popular, but this clock from a school in South Dakota makes a good addition to my man cave.