Sensibly equivalent¶ to:
The 6F5 is classified as a high-μ triode for voltage amplification. It was designed for resistance-capacitance coupled circuits. The 6SF5 is the same valve but the control grid is taken to a base pin not a top cap.
The RCA name and the 6F5 is stamped into the envelope skirt.
Thanks to Mark Mallison for sending these images.
The thin metal tube envelope is 25 mm in diameter and, excluding the IO base pins, is 76 mm tall.
Reference: Datasheet. Type 6F5 was first introduced in 1940.
Absolute Maximum Operating Conditions¶
Updated March 09, 2019. shape:thin.metal.tube construction:glass.disc type:triode age:1930.1940 base:io heater:6.3v pins:8 pin:1.m pin:2.h pin:3.- pin:4.a pin:5.- pin:6.- pin:7.h pin:8.k pin:tc.g1