Original Item. Only One Available. Telephone communication is possible by modulating a lightbeam. The Germans built such a system which can be seen as a predecessor of the fibreoptic techniques of today. Along the Atlantikwall you find many Vf bunkers specially designed for these instruments. Communication with small islands for the coasts was made possible with a small lightbulb of 5 Watts. In the Dutch Scheldt estuary two sets placed in Tobruks were used. But of course the system is light-dependent, so heavy rain and snow causes interruptions. The maximum distance was 4 kilometers. To obscure the transmission at night an infrared filter could be placed. This reduced the range to 2.5 kilometers.
This is a great set of Lichtsprechgerät 80/80 in its original carrying case. The set has a data plate on the front reading:
blc
218124
1940
The Lichtsprechgerät 80 (Light Talk Device 80), abbreviated Li.Spr.80, was a free-space optical communication device, manufactured from 1940 onwards by Carl Zeiss (maker code blc) for use by the German Armed Forces. It uses visible and infrared (IR) light for voice communication (telephony) over distances of up to 10 kilometers. A complete setup consists of a tripod with a dual-lens optical system, and a separate amplifier/power supply unit (PSU) that is connected to the optics via a 2 metre cable.
This set does not include the tripod or the supply unit, so it is more meant for display. However, it does appear to be in full working order from what we can see, so this is a great opportunity to start putting a set together.
These sets are extremely difficult to find, and there isn’t much information on them broadstroke. This would be a great research project. The case retains its original securing straps with springs and is named on the top “BOD.” The case measures 12 x 8 x 5½”. The case is marked blc 42 for the same maker, Carl Zeiss, with a manufacture date of 1942. This case has a different serial number than the set itself.
This set is in great shape overall without any serious issues. Comes ready for further research and display!