Clocks without Tuning Knobs

The first radio time signals were broadcast from Washington, D.C., in 1904. In 1910, a radio transmitter was installed atop the Eiffel Tower in Paris, as well. As a result, it became possible to set clocks to the second; however, this still had to be done manually. In 1967, Wolfgang Hilberg invented a system enabling clocks to set themselves automatically to the correct time.

Ever since 1973, the DCF77 long-wave transmitting station in Mainflingen, near Frankfurt/M., has been sending Central European Time in Hilbergs time code. The transmitter sends complete time and date information every minute.

Radio-controlled clocks became available for personal use beginning in 1986, with radio-controlled wristwatches following in 1990. Once again, Black Forest firms, such as Junghans in Schramberg and Kundo in St. Georgen, were the trendsetters.

Radio-controlled clocks and watches set and adjust themselves by means of a radio receiver. They also switch to Daylight Saving Time automatically. Whenever a radio-controlled clock is not in receiving mode, it keeps time using a quartz movement.