Between 1940 and 1943 the fortress Jutphaas in Holland was part of the U-boat war. Shortly after the occupation of Holland, the Kriegsmarine took over Fortress Jutphaas, 8 km. south of Utrecht, in the center part of Holland.
During 1940 and 1943 Admiral Donitz visited this fort very often.
In 1943 the fortress was attacked by Allied bombers and was never used again by the Kriegsmarine.
Nowadays, little is known about this fortress used for the U-boat war.
During war-time a retractable tower was used for transmitting.
Does anyone know more about frequencies, power equipment, radio's and so on.
For which region in the Atlantic or Baltic Sea this station has been used?

Hereby a photograph of the fortress nowadays:[www.oorlogsmusea.nl]

Thanks for cooperation,
PA3JD Joop
Dedemsvaart