Herzogstand Radio Station was a radio communication station, which was built and operated from 1920 to 1946 at Herzogstand

Herzogstand

The Herzogstand is a mountain in the Bavarian foothills of the Alps, 75 km south of the city of Munich. It has an elevation of 1731 metres and is situated northwest of Lake Walchen. Maximilian II of Bavaria had a hunting lodge built underneath today's so-called Herzogstand-house in 1857. His...

 in the proximity of Kochel/Lake in Bavaria. The plant was conceived of C Lorenz AG as independent operational funds for radio traffic on very long waves between Germany and the far east, since the existing large radio stations served mainly traffic to the west. Starting from 1930 the mechanism was used as research and research station of the technical university Munich for ionosphere

Ionosphere

The ionosphere is a part of the upper atmosphere, comprising portions of the mesosphere, thermosphere and exosphere, distinguished because it is ionized by solar radiation. It plays an important part in atmospheric electricity and forms the inner edge of the magnetosphere...

 research.

Construction of antenna

Since the costs of the masts of a large station of the company were exorbitant, the antenna system in the mountains should be hung up. The 1735 m high Herzogstand between Lake Kochel and Lake Walchen in the Bavarian alps seemed particularly suitable for several reasons: The summit is all year round accessible, at the station place was sufficiently drinking water and cooling water available and the close convenient Lake Walchen Power Plant

Lake Walchen Power Plant

The Walchensee Power Plant is a high pressure storage power station in Bavaria. With an installed output of 124 MW it is today one the largest of its kind in Germany...

 promised a safe, economical power supply. For the intended design of the antenna there were no experiences. As free span a distance of over 2,5 km resulted to reach with a difference in height of 800 m. around a sufficient height of the antenna above ground should the rope at the lower point of suspension horizontally accumulate, which required an enormous tension of the rope. Due to that load by wind, in addition, by snow and ice, additionally which can be expected, only steel wire of highest firmness was applicable. A first thin steel cable became strained in the summer 1920. Radiation measurements resulted in the 1.3 subject radiation and/or the 1.6 subject in the comparison to the overseas Eilvese transmitter

Eilvese transmitter

Eilvese transmitter was a facility of Transradio AG for intercontinental VLF transmission of telegrams at Eilvese, Germany. It went into service in 1913 and used machine transmitters...

 in the case of wavelengths of 12,6 km and 9.7 km in the comparison to the high-power radio station Nauen

Nauen Transmitter Station

Nauen Transmitter Station in Nauen, Havelland , Brandenburg, Germany, is the oldest transmitting plant in the world. It was founded on 1 April 1906 by Telefunken engineer R...

. Up to the early summer 1925 3 antennas were pulled fan-like for the summit burr of the duke conditions. In order to achieve a better conductivity, the steel cable was provided with a coat from aluminum. The rope in a particularly developed Seilereianlage within the summit range were manufactured. In the range of the summit the antennas were fixed at concreted steel anchors. At the lower tie point a mobile suspension was used, in order to make a giving way for that possible rope during load by snow and ice.

Building of transmtter building

The station building for the transmitting plants and a house was established in the long valley above the Kochelsees. Here also extensive grounding systems were built. After the completion a further development and enterprise of the station appeared technical and economically not meaningful, since meanwhile worldwide radio communications on short wave could be accomplished more economically with substantially smaller antennas.

Ionospheric research

The plants were finally placed for research work at the Physical Institute of the Technical University Munich, where under the direction of Professor J. Zenneck, the first German ionosphere research station developed. Using high performance emitters of variable frequencies, scientists investigated the propagation of radio waves and their reflections based on the layers of the ionosphere. But as personal antennas were used, the mountain antenna was again diminished in 1934. The slave station was some km distance away in the "office for amplifier" in Kochel. Occasionally additional transmitting plants in Berlin eagle yard, Amberg and Swan Village were used.

End of facility

After end of the Second World War the ionosphere research was continued until 1946. Subsequently, all plants were diminished, the factory was torn off. Gedenkstein for ionosphere research station today one finds beside Gedenkstein in the proximity of the Walchenseekraftwerkes only remainders of the anchorages to that antenna rope as well as some foundations of the station buildings in the forest.