TM (FOTOS)

The TM (FOTOS) was a triode that was made in France by E.C.& A Grammont using their trademark FOTOS. This was the first tube used by the French military in WWI (1915). Similar tubes were made by the French firm Métal. The TM stands for Télégraphie Militaire.

Length = 4.00" Diameter = 2.12"
Max voltage = 500 (osc)
Max current =
Fil voltage = 4 (as an amp) 5-6 (as an oscillator)
Fil current = .6 - .8         GOTO INDEX