TELEFUNKEN EVE173 VALVE, 1914

Copied and developed by the Germans after they had captured examples of the French hard valve during WW1
This EVE173 has a nickel anode and grid.
Around 1918, because of the shortages of material in Germany, the anodes were made of copper and in some cases the grids as well.
The filament is 0.55amps 2.8volts Anode 40-70 volts.

Nortel Collection

A1308