The German radio navigation system FuSAn 724/725 with the code name "Bernhard" was developed by Telefunken. It could position a plane using radio waves.
The system was started in the autumn 1941 and consisted of a Antenna that was 22 meters in diameter. This rotated about its own axis twice a minute. Each station broadcast a unique radio wave and with only two of these, the individual aircraft could get a very precise position.
In all of Europe, with a distance of 300 km. the germans placed a broadcast station.
The system continued to be develop and expanded throughout the war.
Glau - Germany - 34 km south of Berlin
Favières - France - 20 km northwest of Chartres
Mont Saint Michel de Brasparts - France - 39 km east of Brest
Le-Bois-Julien - France - 35 km south of Calais
La Pernelle - France - 23 km east of Cherbourg
St. Michel mont Mercure - France - 75 km southeast of Nantes
Marlemont - France - 70 km north of Reims
Arcachon - France - 50 km southwest of Bordeaux
Schoorl - Holland - 30 km south of Den Helder
Bredstedt - Germany - 32 km southwest of Flensburg
Hundborg - Denmark - 70 km west of Aalborg
Trebnitz - Poland - 25 km north of Wroclaw
Nevid - Czech Republic - 20 km east of Plzeň
Buke - Germany - 65 km northwest of Kassel
Aidlingen - Germany - 21 km southwest of Stuttgart
Szymbark - Poland - 40 km southwest of Gdańsk
Hornstein - Austria - 40 km south of Vienna