Swisscom-Sendeturm St. Chrischona is a

communications tower Radio masts and towers are typically tall structures designed to support antennas for telecommunications and broadcasting, including television. There are two main types: guyed and self-supporting structures. They are among the tallest human-m ...

built in 1980–1984 near

Basel Basel ( ; ), also known as Basle ( ), ; ; ; . is a city in northwestern Switzerland on the river Rhine (at the transition from the High Rhine, High to the Upper Rhine). Basel is Switzerland's List of cities in Switzerland, third-most-populo ...

, Switzerland, on the territory of the municipality Bettingen,

Basel-Stadt Canton of Basel-Stadt or Basel-City ( ; ; ; ) is one of the 26 cantons forming the Swiss Confederation. It is composed of three municipalities with Basel as the capital. It is traditionally considered a " half-canton", the other half being B ...

. It was built as a replacement for a tall

lattice tower A lattice tower or truss tower is a freestanding vertical latticework, framework tower. This construction is widely used in transmission towers carrying high-voltage electric power lines, in radio masts and towers (a self-radiating tower or as a ...

, which was erected at the site in 1962. This lattice tower was once a part of the famous Beromünster transmitter. The tower is tall – a steel antenna on a concrete base – and not generally accessible for the public, although guided visits can be booked. Apart from

television Television (TV) is a telecommunication medium for transmitting moving images and sound. Additionally, the term can refer to a physical television set rather than the medium of transmission. Television is a mass medium for advertising, ...

FM radio FM broadcasting is a method of radio broadcasting that uses frequency modulation (FM) of the radio broadcast carrier wave. Invented in 1933 by American engineer Edwin Armstrong, wide-band FM is used worldwide to transmit high fidelity, high-f ...

and DAB transmitters, and microwave relays, the tower also contains meteorological instruments, two drinking water tanks, and a meeting/conference room near the top of the concrete structure.

Architecture

The television tower St Chrischona shows some architecturally specific features. It features a "3-leg-construction", in contrast to most other television towers nearby. It has an aerodynamic shape; with a round shaft, the wind from both sides splits and causes, at the rear, an effect that keeps the tower from swaying too strongly. The lower part is star-shaped, and the tower at the apex sways up to even with strong winds. The "Antennenspitze" (round construction method), can sway up to . The

microwave radio relay Microwave transmission is the Data transmission, transmission of information by electromagnetic waves with wavelengths in the microwave frequency range of 300 MHz to 300 GHz (1 m - 1 mm wavelength) of the electromagnetic spectrum ...

antennas are of a height between . VHF antennas are high. Fernsehturm St

On the north side is a construction similar to a "backpack" which has a height of ; and two drinking water tanks that are high that contain water supplies for the municipality of Bettingen. During the construction, the weight of the water had to be included in the tension of the tower, which is why it stood southwardly inclined before the completion. The tower stands on a base construction which includes three basements which accommodate company / technical equipment. As the location of the tower lies in the

seismic zone In seismology, a seismic zone or seismic belt is an area of seismicity potentially sharing a common cause. It can be referred to as an earthquake belt as well. It may also be a region on a map for which a common areal rate of seismicity is assume ...

of Basel – Erdbebengebiet in the Upper Rhine district, this has been built especially securely about the base. The tower should remain stable in an earthquake up to 8 on the

Richter scale The Richter scale (), also called the Richter magnitude scale, Richter's magnitude scale, and the Gutenberg–Richter scale, is a measure of the strength of earthquakes, developed by Charles Richter in collaboration with Beno Gutenberg, and pr ...

. The television tower was under construction from July 1980 until December 1983, and was put into operation on 2 August 1984. It replaced a tall steel radio tower that was built in 1962 in Beromünster, where it carried an antenna for medium wave transmission, like today's backup broadcasting tower. St Chrischona has been in use since 1954, as a broadcasting tower that was tall at that time which transferred Swiss television programmes. Today's tower of St Chrischona carries broadcasting antennas for Swiss Radio (DRS) and "Southwest German Radio" (SWR). Due to the unique construction, it is said that the tower could remain standing during the high winds of a hurricane, where wind speeds appear up to 220 km/h, with an oscillation of only .

Technical data

*The entire height of is divided into a tall shaft with a tower basket and a tall antenna *Architects: Vischer & Weber *Civil Engineer work: Aegerter & Bosshardt *Building cost: 50 million

Swiss franc The Swiss franc, or simply the franc, is the currency and legal tender of Switzerland and Liechtenstein. It is also legal tender in the Italian exclave of Campione d'Italia which is surrounded by Swiss territory. The Swiss National Bank (SNB) iss ...

s *Concrete volume: *Total weight: 23,000 metric tons, of which; 13,500 metric tons are in the foundation and 9,500 metric tons in the tower :*Armouring weight; 1,300 metric tons, steel pipe tower, 135 metric tons :*Steel for the antenna terraces: 120 metric tons, introduction steel: 90 metric tons *Uses :*Transmitter, for among other things, television programmes SF 1 and SF two, the radio programmes DRS 1, DRS 2, DRS 3, Baden-Wurttemberg SWR1, SWR2, SWR 3, Baden-Wurttemberg SWR4, radio Basel 1 and radio basilisk. :*In addition, the tower serves for the radio and phone transference and for the water supply communications. Measuring instruments are, in addition, used for weather forecasting and aerial coordination. In an emergency, the tower can be likewise used as a transmitter.

Broadcast television channels

* for the programs on: SF1, SF2, TSI1, TSR1

Broadcast radio stations

External links

*
Data sheet of the TV Tower St. Chrischona (pdf)
{{Authority control Towers completed in 1984 Towers in Switzerland Buildings and structures in Basel-Stadt 20th-century architecture in Switzerland