BIOS Final Report No. 30

Telefunken Metal/Ceramic Valves*

Reported by

W/Cdr. G.L. Hunt M.A.P.

CIOS Black List Items

No. 1. Radar

Target Nos. 1/18, 1/633




Coaxial ceramic valves were invented and built for the first time in the world by Telefunken during World War Two. In contrast to Allied practice where glass was used, the Germans countered the difficulties incorporated with this kind of technology.


Keywords: Osram; Dr. Kleen, Dr. Pulfrich (wrongly written Pulfrish); Osram factory Sickingenstrasse 71; Dr. Weth; Dr. E. Wiegand; preparation of powder; metallising the ceramic parts; silvering of metal parts; process of soldering; the grid itself is made from molybdenum ... ; cathode .. triple carbonates barium strontium and calcium is used ... ; Ceto getter .. ; Ceto sintering; LD6 - LD7 - LD8 - LD9 - LD11 - LD12 - LG11; when these valves are used without the anode cooling block (see last pages, AOB) they are called LD60-LD70-LD80-LD90-LD110 and LD120 ... ; data sheets ; LD9 S = 20 mA/v (mutual conductance)


*Please notice, that as in most British post war reports, there may exist inconsistencies in the correct spelling of German names and other details



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