KL 42-1 to KL 42-5

The radio was used by artillery for sound ranging enemy artillery. Five sets, KL 42-1 to KL 42-5 were lined up in a row, connected to 5 Microphones. By computing the sound the enemy artillery could be traced. 
It is a solid state radio.

Frequency range:

57 - 51 MHz, in 25- KHz- Steps

Technical data:

Output

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Batteries

3 batteries of 2,4 V