====== Electric watch ======
An **electric watch** is one that uses an electric [[battery]] to charge an electromagnet, which provides mechanical power to a [[balance wheel]]. Electric movements were produced from [[1957]] through the mid 1970s by companies like [[Hamilton]], [[LIP]], [[ETA]], [[Seiko]], and [[Timex]].

===== Early Electric Watches =====
[[LIP]] in France and [[Elgin]] in the United States independently began developing battery electric watches in the late 1940s. Since both were developing similar technology and were challenging Swiss watchmakers, they joined forced, announcing in [[1951]] that they would soon deliver the first electric watch. Development took most of the decade, and [[Hamilton]] was able to deliver the first such watch in [[1957]]. The [[Hamilton Ventura]], famous for its unique case shape and association with American singer Elvis, used a moving coil mounted on the balance wheel. Hamilton later worked with [[Ricoh]] in Japan to create inexpensive electric watch movements.

The LIP/Elgin design, delivered in [[1958]], used a fixed coil on the [[plate]] instead, but required two batteries. It also added a diode to prevent sparking and wear of the contacts. LIP created the first electric dive watch in [[1967]], the [[LIP Nautic-Ski]].

[[ETA]] subsidiary [[Landeron]] created the first Swiss electric movement in [[1961]]. [[Timex]] acquired West German [[Laco]] in [[1962]] to access their high-quality electric movements, though they sold the company to [[ETA]] in [[1965]]. Timex later created their own simple and durable electric movement, which would continue in production for a decade.

[[Léon Hatot]] of France invented a system that used induction in a coil to trigger a transistor to energize the electromagnetic coil. This eliminated the problematic contacts of earlier designs, improving reliability. This was licensed by many makers in later years, and the "ATO" mark seen on their movements is a reference to Hatot. [[ESA]]'s [[Dynotron]] was the first production transistorized electric watch movement in [[1967]], and these were widely used by Swiss watch manufacturers. [[Derby]] was another manufacturer within [[Ebauches SA]] that made electric movements, and theirs took the [[Swissonic]] name, which was also applied to [[tuning fork]] ("[[Mosaba]]") and [[quartz]] movements in the 1970s.


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