Sensibly equivalent¶ to:
The L63 was an Octal based general purpose amplifier triode from M-OV - here with the Osram brand label. It featured the then (1938) new standard 6.3 Volt heater. This was a low power heater insulated with alumina.
L63 is taller and features an all plastic base cap, this example has a metal skirt to the base and looks earlier. Through the glass can be seen the flat anode.
The Osram label. Through the glass the side of the anode can be seen, also the 'fingers' holding the top mica in place. These four metal strips make contact with the inner coating. It is possible that this is a carbon deposit and acts as an internal screen.
The wide glass tube envelope is 28 mm in diameter and, excluding the IO base pins, is 76 mm tall.
References: Private communication, data-sheet & 1043. Type L63 was first introduced in 1938.
Absolute Maximum Operating Conditions¶
Updated September 18, 2020. shape:wide.glass.tube construction:pinch type:triode age:1930.1940 base:io heater:6.3v pins:8 pin:1.m pin:2.h pin:3.a pin:4.- pin:5.g1 pin:6.- pin:7.h pin:8.k