Transmitter Navy, LO 40 K 39, from C Lorenz AG Berlin, Tempelhof.


This navy transmitter was in use by the former German Kriegsmarine, on board of battle ships. Some times in use as a spare transmitter on board of submarines. Even in use in the dessert sometimes.


A very rare picture of the LO40K39 in use in the dessert. Left the power supply, to the right the transmitter. As a receiver, the Tornistor Empfanger b is used. This more powerful  transmitter was used, because distances became too large for the normal in use transmitters.

It contains three RL12P35 valves. One for the variabel oscillator stage and two in parallel for the power amplifier stage. Mine delivers about max. 100 watts output power on CW only.

LO 40K 39 front

Above the transmitter and below the power supply of mine.

Picture 004

Above the back view.

The right part is the oscillator stage, the mid unit is the power amplifier and the left unit the aerial matching part.

Picture 005

A clear view from above. Notice, that all tuned  circuits are variometer coils. The coils are fastened on ceramic holder for maximum frequency stability. Also complex circuit of special ceramic condense are included in these circuits. This also, to establish a great frequency stability.


Above the power amplifier valves, type RL12P35.


Above the aerial matching. A switch , with slide contacts on this coil e, seen on the picture, establish a good match on the aerial, a inverted L-aerial.


A good detailed picture of the oscillator stage. Tuning the frequency is done by a variometer circuit on a ceramic coil holder. An amazing design.

Kopie van LO 40 K 39a a

The data sheet of the transmitter. In this case both the transmitter and power supply are housed in the same cabinet. Often are housed in separate housings.


This is the original cable between the power supply and the transmitter of mine.. which is unfortunately not mine. I had to make mine of my own.  Maybe someone?


The schematic diagram of the transmitter, a type d.


The transmitter working with the LO6K39 receiver, above  Radione R3 receiver, which also could be used.

Posted in Army Navy, German Army Navy.

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