Telechron (Warren Telechron Company)
The Massachusetts company that taught power stations to keep time, so that a clock plugged into the wall could keep it too.
An engineer's hobby in Ashland
Telechron grew out of one engineer's hobby. Henry Ellis Warren was born in Boston in 1872 and graduated from MIT in 1894, according to the Engineering and Technology History Wiki of the IEEE. After about five years as an engineer for the Saginaw Valley Traction Company in Michigan, he joined the Lombard Governor Company in 1902 and spent roughly 16 years there as an engineer and general superintendent.
Lombard moved its factory from Boston to Ashland, Massachusetts, in 1904, and Warren settled on a farm in Ashland in 1907, where he built electric clocks in his spare time. In 1912 he organized the Warren Clock Company to make and sell battery-powered clocks. He went on to hold more than 100 patents, serve as president of the Warren Telechron Company and work as a consulting engineer for General Electric.
The synchronous motor and the master clock
From 1916 Warren worked on keeping time with ordinary alternating current. The result was a small self-starting synchronous motor, which the Smithsonian says he patented in 1918. Because such a motor turns in step with the power supply, a clock driven by it is only as steady as the frequency of the grid.
That was the catch. Power companies of the day let their frequency drift, and the Ashland Historical Society quotes Warren admitting that his early clock was off by as much as 10 or 15 minutes a day. His answer was the Warren Master Clock, an instrument that let a power station check and correct its frequency against true time.
The IEEE history says the Edison Electric Illuminating Company of Boston became the first utility to regulate its frequency this way, in 1916, and that within about a decade regulated AC had become a common basis for timekeeping. It adds that electric clocks rose from under 2 percent of non-alarm clocks sold each year in 1916 to more than 60 percent by 1933. Warren received the AIEE Lamme Medal in 1934 for this work.
See also: where the time on your devices really comes from on OnlineClock.app.
General Electric and the Telechron name
General Electric invested early. The Ashland Historical Society says GE bought a half interest in 1917, while the Smithsonian gives the stake as 49 percent. The firm became the Warren Telechron Company in 1926, and in 1927 GE financed a new factory at Union Street and Homer Avenue in Ashland, a building that still stands.
From about 1930, GE-branded clocks made in Ashland appeared alongside Telechron-branded ones, according to the Smithsonian. When Warren retired in 1943, GE took a controlling interest, and the historical society says GE later used the Telechron name alone. The Smithsonian says GE stopped making electric clocks in 1979, and the historical society says GE closed its Ashland operations in the late 1970s. Warren died in 1957, holding 135 US patents by the society's count.
How to recognize a Telechron clock
A 1930s Telechron alarm clock in the Smithsonian's National Museum of American History shows typical features. Its movement was made in Ashland, and its art deco case, metal with a black plastic base made by the Dura Company of Toledo, Ohio, was based on a 1931 design patent. The museum's record lists both Warren Telechron Co. and General Electric as makers.
That clock also has a small window under the 12 that shows a red dot when the power has been interrupted. Resetting the clock makes the dot disappear, a handy reminder that the time shown may be wrong.
Because GE-branded clocks were also made in Ashland from about 1930, the maker's name on the dial is not the whole story; the movement's origin matters too. Remember that any synchronous clock needs the mains frequency it was built for to keep correct time.
Questions people ask
Who made Telechron clocks?
The Warren Telechron Company of Ashland, Massachusetts, founded by Henry E. Warren, with General Electric as a major investor from 1917 and controlling owner from 1943.
Is Telechron still in business?
No. According to the Smithsonian, General Electric stopped making electric clocks in 1979, and the Ashland Historical Society says GE closed its Ashland operations in the late 1970s.
What does the red dot on my Telechron mean?
On models that have it, a red dot in a small window under the 12 means the power was interrupted. Resetting the clock clears it.