Valvola 25L6GT Foto originali Zoccolo Octal (Int.Octal, IO) K8A, USA 1935 (Codex=Udb) Utilizzata per Radio/TV-reception etc. Filamento Vf 25 Volt / If 0.3 Ampere / Indirect / Specified current AC/DC ~ = (Series working) Descrizione The octal-based (EIA base 7AC) beam power tetrode 25L6 was mainly used for the "All American Five" type radios, in short "AA5" sets abut also in a number of early computers, like the UNIVAC I (1952) from Remington Rand (later called Sperry Rand and then Unisys). The UNIVAC I used about 5200 vacuum tubes. The tube type 6046 is the industrial type of the 25L6GT, used as a relay driver or to run selenoids in key punch machines. The 25L6 was introduced as a metal tube November 4, 1936, but most examples of this family were glass types 25L6G or 25L6GT. The ST14 glass tube 25L6G started March 30, 1937. The T9 size GT version arrived the market April 11, 1938. There was also a 25L6G in the smaller ST-12 glass envelope. The 25L6 is identical in design and ratings with the 50L6 except haveng a 25 volt 300 mA heater instead of a 50 volt 150 mA heater. The 12L6 and an identical 12W6 were made with a 12.6 volt, 600 mA heater, and the 6W6 was made with a 6.3V, 1200 mA heater. A bit different (slightly lower-powered heater) is the otherwise same 35L6, but the 6L6 with the same basing diagram is not of this family and has more than twice the power capability of the family.