1967 Bulova Accutron Men's Calendar 2181 Silver Watch w/ Strap
This watch is in Excellent Pre-Owned condition
PLEASE REFER TO THE PICTURES
The Bulova Accutron was the world's first electronic watch. People sometimes refer to the Accutron as the worlds first electric watch. This isn't quite true but as it was the first to use a bipolar transistor it certainly deserves the former accolade. The first Accutron was manufactured in 1960 and was the watch chosen by some of the 'Original Seven' NASA astronauts to accompany man on his first journeys into space.
the watch uses a tuning fork as its prime moving element. It is a well understood physical principle that the faster your initial reference the more accurate your time keeping will be. The most accurate clocks nowadays use the vibrations of a caesium atom as their reference. In the 1950s the best mechanical watches could rely on a prime moving element with a frequency of around 2 Hz (That is two 'beats' per second). Max Hetzel an engineer employed by the Bulova Watch Company of Bienne Switzerland designed an electrically excited tuning fork movement with a a frequency of 360 Hz. Bulova claimed an accuracy of 2sec per day or 1 min per month. This was the only movement capable of the accuracy demanded by spaceflight. Accutrons were used as time references in many satellites and also to control some of the Apollo moon experiments.The Tuning Fork Movement is absolutely unique in operation emitting a distinctive hum and featuring a sweep seconds hand. Here's a reproduction of an advertisement produced by Bulova in the early 1960s.
Some Accutron Facts (Engineers take note this was achieved in 1960!!)
- The index wheel boasts 320 teeth each of which is ten microns in depth
- For a thirty year old watch this means that over 2.8 E+11 teeth have have moved under the pawl jewel.
- The Accutron was used to correctly dimension Greenland for the first time.
- Each coil boasts 8000 turns of wire, the diameter of which is 15 microns.
- Assertions movements were used in the Apollo space craft panel clocks.
- The Bulova Accutron was the first wristwatch to utilize a Bipolar Transistor.
This Unique and Beautiful Accutron has Silver-tone case and Strap
Beautiful Dial features Original Silver-tone Hands and Silver-tone hour Markers at all hour positions.
Case measures 33.5mm diameter excluding crown
Watch comes with Strap
Watch comes without box and papers