Friday, March 02, 2007

The Eiffel Tower is an Antenna

The Eiffel tower in Paris was built for an Exhibition in celebration of the French Revolution. Construction began earnestly in 1884 and about 2 years and 7,000+ tons of iron later it was finished. It was purely decorative for the first 20 years. Then it became the most famous broadcasting mast in the world.

Since the turn of the century (not that one, the one before that) the tower has been used for radio transmission. The first signals were sent from the Eiffel in 1898! Eugène Ducretet successfully sent these first radio signals to the Pantheon. He took that to the French military authorities in 1901 with a plan to make the Tower into a long-distance radio antenna. thaty liked the idea a bunch. By 1903 a radio connection was made with the military bases around Paris, and then a year later with the East of France. A permanent radio station was installed in the Tower in 1906.

On 20 November 1913 the Paris Observatory, used the Eiffel Tower as an antenna, exchanging wireless signals with the United States Naval Observatory in Arlington, Virginia. The object of the transmissions was to measure the difference in longitude between Paris and Washington, DC. These shortwave broadcasts continued into the 1950s. In 1957 the set of antenna wires the ran from the summit to anchors on the Avenue de Suffren and Champ de Mars were removed. They were connected to long-wave transmitters in small bunkers. In 1957, the tower started transmitting both FM radio and television.

In 1921 when a radio studio was opened in the tower transmissions of the first French radio station, Radiola Paris began. They beat the BBC to the air by one week. In 1924 it changed its name to Radio Paris.

Today the Eiffel Tower has a 70-feet antenna on the very top which makes its height 1,070 feet. Today there is still a radio studio which is underground and near one of the four legs. There are other rooms for the actual transmitters at the top. The transmitter tower is still in active use for FM radio broadcast. Eiffel lived long enough to hear the first European public radio broadcast from an aerial on the Tower in 1921.